I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

On Mon, 07 Oct 2013 21:08:54 -0500, Ignoramus3720
wrote:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i
Any squeaks? Particularly backing up slowly? Any "clunk" starting in
either direction. If so, suspect a "U" joint. If you have a bad one,
change them all at once.

On Mon, 07 Oct 2013 22:24:33 -0400, wrote:

On Mon, 07 Oct 2013 21:08:54 -0500, Ignoramus3720
wrote:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i
Any squeaks? Particularly backing up slowly? Any "clunk" starting in
either direction. If so, suspect a "U" joint. If you have a bad one,
change them all at once.

I'll second all of that.

--
Win first, Fight later.

--martial principle of the Samurai

Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i


Could be u-joints . Easy to check - put the parking brake on , gear shift
in neutral . Might want to chock the wheels , I don't usually . Slide under
the truck and rotate/shake the driveline . If you see movement in the joint
it's shot .
--
Snag

On Mon, 7 Oct 2013 22:20:59 -0500, "Snag" wrote:

Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i


Could be u-joints . Easy to check - put the parking brake on , gear shift
in neutral . Might want to chock the wheels , I don't usually . Slide under
the truck and rotate/shake the driveline . If you see movement in the joint
it's shot .
It can be shot with no appreciable looseness. The joint can be tight
instead of loose and still cause a shake. Generally these squeak, or
"chirp"

On Monday, October 7, 2013 7:08:54 PM UTC-7, Ignoramus3720 wrote:
I have a problem...

That's the first step toward recovery. In your case you still have a long, long way to go.

In article , "Snag"
wrote:

Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i


Could be u-joints . Easy to check - put the parking brake on , gear shift
in neutral . Might want to chock the wheels , I don't usually . Slide under
the truck and rotate/shake the driveline . If you see movement in the joint
it's shot .

From what you said I suspect it's wheel related. Out of balance tires
often act up within certain speed 'bands'.

If wheel speed vibration frequency sounds right, look for loose lugs and
missing wheel weights (there will usually be a dirt 'witness mark' on
the rim where a lost weight was). Look at both sides, inside and out.
Look over the wheels/tires for obvious things like ply separations, wads
of stuck on spooge or whatnot.

A bad front wheel bearing/s can sometimes produce vibrations that vary
with vehicle speed... and as they get worse can even induce an eerie low
pitch 'humming' like sound into the vehicle. I haven't run into many of
these, but the ones I have were more felt than heard, and sometimes
seemingly originate from 'everywhere'.

If after all the driveshaft is suspected, go under shake/wiggle as
mentioned above looking for joint slop. (RWD driveshafts rotate much
faster than wheels, so if responsible, the frequency will be a good bit
faster.)

If you can quickly (and safely) dash under the truck immediately after
driving, feel for hot bearing cups. Use caution, a bad one might be
quite hot.

If so equipped, look at the shaft center support & bearing... check it
for mounting security and bearing slop.

Look over the shaft itself for stuck on spooge, foreign matter like
rope, extension cord or the like wrapped around, missing bolts, physical
damage etc.

Also, some vehicles have a fair sized weight bolted to the transmission
output shaft housing to 'soak up' vibration. If you have one, be sure
it's tight. While there, grab the output housing or front of the drive
shaft, shake and check for a busted or sloppy rear engine mount.

Not a bad idea to look over all this stuff whenever your down there,
vibration or not. Just look over every thing in general with an emphasis
on delicate stuff, like brake hoses/lines, exposed wiring & connectors,
CV boots and on and on.

Good luck, let us know how it turns out.

Erik

"Ignoramus3720" wrote in message
...
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?


Your transmission is going out, not worth fixing, time to scrap it and find
a new truck

On Mon, 07 Oct 2013 19:54:25 -0700, Larry Jaques
wrote:

On Mon, 07 Oct 2013 22:24:33 -0400, wrote:

On Mon, 07 Oct 2013 21:08:54 -0500, Ignoramus3720
wrote:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i
Any squeaks? Particularly backing up slowly? Any "clunk" starting in
either direction. If so, suspect a "U" joint. If you have a bad one,
change them all at once.

I'll second all of that.

Me three.


"The socialist movement takes great pains to circulate frequently new labels for its ideally constructed state.
Each worn-out label is replaced by another which raises hopes of an ultimate solution of the insoluble basic
problem of Socialism, until it becomes obvious that nothing has been changed but the name.
The most recent slogan is "State Capitalism."[Fascism] It is not commonly realized that this covers nothing more
than what used to be called Planned Economy and State Socialism, and that State Capitalism, Planned Economy,
and State Socialism diverge only in non-essentials from the "classic" ideal of egalitarian Socialism. - Ludwig von Mises (1922)

Erik fired this volley in news:spam-984467.22445207102013
@news.dslextreme.com:

From what you said I suspect it's wheel related. Out of balance tires
often act up within certain speed 'bands'.



Really? Even when he said it ONLY happens when accelerating in that speed
band, but not when coasting or decelerating?

Unless he's got a horrible tread separation, there's no "drive vs. coast"
defect I'm aware of in tires that could cause that symptom.

Lloyd

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

In addition to the suggestions about U-joints and trannies (but not
tires), It could be a torque/speed problem related to the engine
performance. It might be missing at a certain torque and speed AND
vehicle speed range.

I lean more toward it's being a tranny problem.

When's the last time you completely drained, flushed, and re-filled the
transmission?

Lloyd

"Erik" wrote in message
...
In article , "Snag"

wrote:

Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate.
What could it be?

i

From what you said I suspect it's wheel related. Out of balance
tires
often act up within certain speed 'bands'.

Erik

I had a puzzling speed-related vibration problem that turned out to be
a rusted-out upper shock mount in the front. It's out of sight behind
a flange on the spring mount so I only found it when I bumped the
shock and it moved. Other than a slight steering wheel shake at
certain speeds the truck handled normally.

The factory manual says when replace the rivets holding such things to
the frame with bolts, use Grade 8 one size larger.

jsw

On Tue, 08 Oct 2013 05:35:29 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Erik fired this volley in news:spam-984467.22445207102013
:

From what you said I suspect it's wheel related. Out of balance tires
often act up within certain speed 'bands'.



Really? Even when he said it ONLY happens when accelerating in that speed
band, but not when coasting or decelerating?

Unless he's got a horrible tread separation, there's no "drive vs. coast"
defect I'm aware of in tires that could cause that symptom.

Lloyd
A relatively minor tread separation CAN cause an under-load shake -
but will usually also shake under moderate braking.

On Tue, 08 Oct 2013 05:38:36 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

In addition to the suggestions about U-joints and trannies (but not
tires), It could be a torque/speed problem related to the engine
performance. It might be missing at a certain torque and speed AND
vehicle speed range.

I lean more toward it's being a tranny problem.

When's the last time you completely drained, flushed, and re-filled the
transmission?

Lloyd
We are talking about the old horses vs zebras vs unicorns thing here
again.

Check for horses first. For all it takes to pull a driveshaft, just
pop it out and chech each joint for play/stiffness. Mabee half an
hour's work on a bad day? And if the joints are bad, you have 1/4 of
the work done already.

wrote in message
...
It can be shot with no appreciable looseness. The joint can be tight
instead of loose and still cause a shake. Generally these squeak, or
"chirp"

Can you generally tell by unbolting the flange and wiggling the
u-joint by hand?

The few I've worked on were pretty obviously bad once freed from the
tranny or differential. The OEM ones were "lubed for life", so their
life ended when the lube ran out.

I've heard that sticky driveshaft slip joint splines can cause strange
symptoms.

jsw

On Tue, 08 Oct 2013 05:38:36 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

In addition to the suggestions about U-joints and trannies (but not
tires), It could be a torque/speed problem related to the engine
performance. It might be missing at a certain torque and speed AND
vehicle speed range.

I lean more toward it's being a tranny problem.

When's the last time you completely drained, flushed, and re-filled the
transmission?

Since it's not a Ford, with their damnable 4sp OD tranny, I strongly
doubt it. Mine felt like it was missing in 4th at 75 during heavy
accelleration.


--
Win first, Fight later.

--martial principle of the Samurai

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i



What kind of truck, age, mileage, engine size and all?

I've been thinking about this, last few hours. With
the "worse on accel", it sounds familiar. One email
friend of mine suggests it might be tune up and
ignition related. Might be missing on one cylinder,
which is worse on accel (timing advance).


..
Christopher A. Young
Learn about Jesus
www.lds.org
..

On 2013-10-08, Stormin Mormon wrote:
Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i



What kind of truck, age, mileage, engine size and all?

I've been thinking about this, last few hours. With
the "worse on accel", it sounds familiar. One email
friend of mine suggests it might be tune up and
ignition related. Might be missing on one cylinder,
which is worse on accel (timing advance).

Certainly a possibility.

i

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

Vibration on accel occurs when the distributor
vacuum advance is activated. I'd be looking at
ignition wires, spark plugs, etc.

--
..
Christopher A. Young
Learn about Jesus
www.lds.org
..

On Monday, October 7, 2013 10:08:54 PM UTC-4, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.



The problem is that at certain speeds, such as 40-45 MPH, I feel

vibration if I step on the gas pedal and try to accelerate. If I let

go of the gas pedal, vibration stops even as the truck continues to

drive forward. It has gotten worse lately. I have thought a lot on

what could cause it. It does not seem to be related to the engine

RPM. I watch the RPM vary and the vibration does not vary with it.



What could it be?



i

In the could-also-be-in-addition-to-what's-been-mentioned department...

Depending on the pickup, if it has a 2-piece driveshaft with a carrier the carrier bearing could be shot, or just the rubber supporting he carrier could be shot. Usually midsize pickups are the biggest with this arrangement, so probably not relevant.

Could also be a worn out slider (where it fits into the trans with a 1-piece shaft), or just bad output bearings in the trans.

Dave

On Tue, 8 Oct 2013 08:38:50 -0400, "Jim Wilkins"
wrote:

wrote in message
.. .
It can be shot with no appreciable looseness. The joint can be tight
instead of loose and still cause a shake. Generally these squeak, or
"chirp"

Can you generally tell by unbolting the flange and wiggling the
u-joint by hand?

The few I've worked on were pretty obviously bad once freed from the
tranny or differential. The OEM ones were "lubed for life", so their
life ended when the lube ran out.

I've heard that sticky driveshaft slip joint splines can cause strange
symptoms.

jsw

Can virtually always feel it when unbolted.

On Tue, 08 Oct 2013 09:13:48 -0400, Stormin Mormon
wrote:

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i



What kind of truck, age, mileage, engine size and all?

I've been thinking about this, last few hours. With
the "worse on accel", it sounds familiar. One email
friend of mine suggests it might be tune up and
ignition related. Might be missing on one cylinder,
which is worse on accel (timing advance).


.
Christopher A. Young
Learn about Jesus
www.lds.org
.
Looking for unicorns again, stormy. Or at least Zebras.

If you want to look for Zebras I've got another one for you. I
started feeling a bit of a shake at 95Kph recently on my Ranger. Not
consistant - and it went away when I backed out of the throttle or
declutched. Dead smooth when declutched. Checked the tires last
evening and guess what I found? One rear tire was about 10psi low -
and the truck has posi. Aired up, and no more shake on accelleration.

Not a horse, but not a unicorn either.
Mabee not a zebra - mabee a mule???

On Tue, 08 Oct 2013 17:22:57 -0400, Stormin Mormon
wrote:


The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

Vibration on accel occurs when the distributor
vacuum advance is activated. I'd be looking at
ignition wires, spark plugs, etc.
How old is the vehicle to still have vacuum advance????

Have not seen what make and model vehicle are we talking about???
There are some things that are very common on one vehicle that you
might never see on another one.

On Tue, 8 Oct 2013 14:40:59 -0700 (PDT), wrote:

On Monday, October 7, 2013 10:08:54 PM UTC-4, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.



The problem is that at certain speeds, such as 40-45 MPH, I feel

vibration if I step on the gas pedal and try to accelerate. If I let

go of the gas pedal, vibration stops even as the truck continues to

drive forward. It has gotten worse lately. I have thought a lot on

what could cause it. It does not seem to be related to the engine

RPM. I watch the RPM vary and the vibration does not vary with it.



What could it be?



i

In the could-also-be-in-addition-to-what's-been-mentioned department...

Depending on the pickup, if it has a 2-piece driveshaft with a carrier the carrier bearing could be shot, or just the rubber supporting he carrier could be shot. Usually midsize pickups are the biggest with this arrangement, so probably not relevant.

Could also be a worn out slider (where it fits into the trans with a 1-piece shaft), or just bad output bearings in the trans.

Dave
Or a bad trans mount. Again - what year, make, and model???

On Monday, October 7, 2013 8:08:54 PM UTC-6, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck. The problem is that at certain speeds, such as 40-45 MPH, I feel vibration if I step on the gas pedal and try to accelerate. If I let go of the gas pedal, vibration stops even as the truck continues to drive forward. It has gotten worse lately.. I have thought a lot on what could cause it. It does not seem to be related to the engine RPM. I watch the RPM vary and the vibration does not vary with it. What could it be? i

Worn suspension arm bushings caused that in my case, the upper suspension arm bonded bushings had deteriorated to the point where there was only shreds of rubber left. The lowers still had the rubber but the bonding to the inner sleeve was gone. I had another vehicle that still had the original factory tie rod ends, these were also bonded rubber and had gone away. Only rattled at certain speeds and really didn't affect steering, somehow. The parts for these replacements were pretty cheap, had to have a heavy press to replace the bushings. Have had to do this now on several vehicles since I tend to run them until they go to the junkyard. Upper bushings are hard to see on a lot of vehicles, hard to get to, too. Bum ball joints will do this, also, but you usually get a vague drifting feel with the steering when that happens. So check your suspension. Only real way I know of is to detach the upper ball joint, get the spring out and see if there's play on arms or ball joints. Now that I know how, I can usually do both ball joints and bushings on a Sat. Don't go for super-cheap suspension parts or you'll get to do it again quite soon.

I've had regular Hooke's u-joints go bad with the needles rusted out and gone, never really had any vibration at speed but had a loud clunk when shifting into reverse, this was on an old IH Scout with a three-speed manual and 4WD. Never really caught on until I downshifted on the highway and the stubs broke off on the cross on the front joint. Very noisy. Was my dad's truck when I was a teen and he plowed all winter with it. Didn't get much maintenance in sub-zero. You should be able to check for u-joint play by jacking up a rear wheel and twisting the drive shaft back and forth by hand.

I've also see vibration checked for by putting the vehicle on a lift with the wheels free and running it up to speed with a mechanic looking underneath for drivetrain vibration. It's a last resort, very dangerous, stay clear because rocks can come flying out of the tire treads. If no vibration that way, it's got to be suspension or front wheel bearings.

Stan

On 9/10/2013 4:39 PM, wrote:
On Monday, October 7, 2013 8:08:54 PM UTC-6, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck. The problem is that at certain speeds, such as 40-45 MPH, I feel vibration if I step on the gas pedal and try to accelerate. If I let go of the gas pedal, vibration stops even as the truck continues to drive forward. It has gotten worse lately. I have thought a lot on what could cause it. It does not seem to be related to the engine RPM. I watch the RPM vary and the vibration does not vary with it. What could it be? i

Worn suspension arm bushings caused that in my case, the upper suspension arm bonded bushings had deteriorated to the point where there was only shreds of rubber left. The lowers still had the rubber but the bonding to the inner sleeve was gone. I had another vehicle that still had the original factory tie rod ends, these were also bonded rubber and had gone away. Only rattled at certain speeds and really didn't affect steering, somehow. The parts for these replacements were pretty cheap, had to have a heavy press to replace the bushings. Have had to do this now on several vehicles since I tend to run them until they go to the junkyard. Upper bushings are hard to see on a lot of vehicles, hard to get to, too. Bum ball joints will do this, also, but you usually get a vague drifting feel with the steering when that happens. So check your suspension. Only real way I know of is to detach the upper ball joint, get the spring out and see if there's play on arms or ball joints.
Now that I know how, I can usually do both ball joints and bushings on a Sat. Don't go for super-cheap suspension parts or you'll get to do it again quite soon.

I've had regular Hooke's u-joints go bad with the needles rusted out and gone, never really had any vibration at speed but had a loud clunk when shifting into reverse, this was on an old IH Scout with a three-speed manual and 4WD. Never really caught on until I downshifted on the highway and the stubs broke off on the cross on the front joint. Very noisy. Was my dad's truck when I was a teen and he plowed all winter with it. Didn't get much maintenance in sub-zero. You should be able to check for u-joint play by jacking up a rear wheel and twisting the drive shaft back and forth by hand.

I've also see vibration checked for by putting the vehicle on a lift with the wheels free and running it up to speed with a mechanic looking underneath for drivetrain vibration. It's a last resort, very dangerous, stay clear because rocks can come flying out of the tire treads. If no vibration that way, it's got to be suspension or front wheel bearings.

Stan



........... or a front tyre issue (I just had one!)

I thought I had a wheel bearing problem in front RHS. Felt ok by hand
when jacked up but made noise at, and varied with speed. I got a
puncture in the RHF & the noise disappeared when the spare was fitted to
the RHF. Tyre looks ok, seems to run true & is balanced. Beats me why
its noisy. I've put it on the rear and don't notice any noise now.

On Wed, 09 Oct 2013 20:37:37 +0800, Glenn B
wrote:

On 9/10/2013 4:39 PM, wrote:
On Monday, October 7, 2013 8:08:54 PM UTC-6, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck. The problem is that at certain speeds, such as 40-45 MPH, I feel vibration if I step on the gas pedal and try to accelerate. If I let go of the gas pedal, vibration stops even as the truck continues to drive forward. It has gotten worse lately. I have thought a lot on what could cause it. It does not seem to be related to the engine RPM. I watch the RPM vary and the vibration does not vary with it. What could it be? i

Worn suspension arm bushings caused that in my case, the upper suspension arm bonded bushings had deteriorated to the point where there was only shreds of rubber left. The lowers still had the rubber but the bonding to the inner sleeve was gone. I had another vehicle that still had the original factory tie rod ends, these were also bonded rubber and had gone away. Only rattled at certain speeds and really didn't affect steering, somehow.

Amazing. It should have been wandering all over the road after you
hit even a slight bump.


The parts for these replacements were pretty cheap, had to have a heavy press to replace the bushings. Have had to do this now on several vehicles since I tend to run them until they go to the junkyard. Upper bushings are hard to see on a lot of vehicles, hard to get to, too. Bum ball joints will do this, also, but you usually get a vague drifting feel with the steering when that happens. So check your suspension. Only real way I know of is to detach the upper ball joint, get the spring out and see if there's play on arms or ball joints.
Now that I know how, I can usually do both ball joints and bushings on a Sat. Don't go for super-cheap suspension parts or you'll get to do it again quite soon.

Amen to that.


I've had regular Hooke's u-joints go bad with the needles rusted out and gone, never really had any vibration at speed but had a loud clunk when shifting into reverse, this was on an old IH Scout with a three-speed manual and 4WD. Never really caught on until I downshifted on the highway and the stubs broke off on the cross on the front joint. Very noisy. Was my dad's truck when I was a teen and he plowed all winter with it. Didn't get much maintenance in sub-zero. You should be able to check for u-joint play by jacking up a rear wheel and twisting the drive shaft back and forth by hand.

I heard a Mexi-mobile (some funky old chebby) take off from a parking
lot once. EEK-OOK-EEK-OOK-EEK-OOK from zero to 15mph or so. Must have
driven the driver crazy. It was a pole-vaulting event waiting to
happen. When front u-joints let go, it can make for spectacular
crashes on the freeway.

I had a truck's rear u-joint go while I was following it once. The
center flew out and hit my windshield right between my eyes. Luckily,
it was spinning beneficially to the slant of the windshield, so my
F-150 glass only got a shearing scratch there, no puncture. Most of
it polished out. I was -really- lucky that day. A truck cross through
the forehead would have kinda hurt. I avoided the drive shaft which
the truck jumped over because I was in the next lane over by that
time. Talk about adrenaline shakes...


I've also see vibration checked for by putting the vehicle on a lift with the wheels free and running it up to speed with a mechanic looking underneath for drivetrain vibration. It's a last resort, very dangerous, stay clear because rocks can come flying out of the tire treads. If no vibration that way, it's got to be suspension or front wheel bearings.

Stan



.......... or a front tyre issue (I just had one!)

I thought I had a wheel bearing problem in front RHS. Felt ok by hand
when jacked up but made noise at, and varied with speed. I got a
puncture in the RHF & the noise disappeared when the spare was fitted to
the RHF. Tyre looks ok, seems to run true & is balanced. Beats me why
its noisy. I've put it on the rear and don't notice any noise now.

Prolly ply sep in the tread area. They're easier to diagnose in the
sidewall, where you can physically see them through the thinner rubber
layer.

--
Win first, Fight later.

--martial principle of the Samurai

I investigated this further. The drive shaft (prop shaft) does not
appear to be loose.

The vibration seems to be related to a gear. If I drive wnd watch RPM,
at around 35 MPH, the vibration starts as soon as the RPM drops,
indicating a gear change. Again, it only appears when I push on gas,
and seems to be further limited to that gear.

i

On 2013-10-08, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

I had a truck's rear u-joint go while I was following it once. The
center flew out and hit my windshield right between my eyes. Luckily,
it was spinning beneficially to the slant of the windshield, so my
F-150 glass only got a shearing scratch there, no puncture. Most of
it polished out. I was -really- lucky that day. A truck cross through
the forehead would have kinda hurt. I avoided the drive shaft which
the truck jumped over because I was in the next lane over by that
time. Talk about adrenaline shakes...

Reminded me of this video:

http://www.youtube.com/watch?v=rOhgMAOrp0c

As a kid I remember my dad coming home one day and telling us of a lost
driveshaft scare he's had... IIRC he said it came from the opposite side
of the freeway bouncing/flailing end over end through traffic, hopped
the center divider for another bounce or two before impaling itself
javelin style into an ice-plant covered embankment.

I've heard, (but don't know to be fact) that US Federal Motor Vehicle
Safety Standards now require vehicles contain and prevent driveshaft
separation in the event of joint failure.

Erik

"Ignoramus27351" wrote in
message ...
I investigated this further. The drive shaft (prop shaft) does not
appear to be loose.

Mine didn't either. IIRC wiggling a jacked-up tire showed the loose
u-joint better than trying to turn the driveshaft when the wheels were
on the ground and the parking brake applied. Unbolting it was even
better but I had to go out to buy a 12mm 12 point flex socket to get
the front one off, and more importantly to torque it back on.
jsw

On 09/10/13 17:49, Erik wrote:
I had a truck's rear u-joint go while I was following it once. The
center flew out and hit my windshield right between my eyes. Luckily,
it was spinning beneficially to the slant of the windshield, so my
F-150 glass only got a shearing scratch there, no puncture. Most of
it polished out. I was -really- lucky that day. A truck cross through
the forehead would have kinda hurt. I avoided the drive shaft which
the truck jumped over because I was in the next lane over by that
time. Talk about adrenaline shakes...
Reminded me of this video:

http://www.youtube.com/watch?v=rOhgMAOrp0c

As a kid I remember my dad coming home one day and telling us of a lost
driveshaft scare he's had... IIRC he said it came from the opposite side
of the freeway bouncing/flailing end over end through traffic, hopped
the center divider for another bounce or two before impaling itself
javelin style into an ice-plant covered embankment.

I've heard, (but don't know to be fact) that US Federal Motor Vehicle
Safety Standards now require vehicles contain and prevent driveshaft
separation in the event of joint failure.

Erik
When I was living in Wichita around 1981 a woman was killed when a IIRC
plastic drain fitting fell off another vehicle and smashed through her
windscreen. I myself have received minor facial cuts when a rock was
jettisoned from a tipper truck, possibly having been stuck between the
twin rear wheels, hit the back edge of the bonnet (US hood) and smashed
the windscreen in front of me puncturing the laminated interlayer,
fortunately I saw it coming in time the shut my eyes. Luckily no one
else was in the car as they would have been showered in glass shards. I
was surprised just how much glass was in the car from front to back, it
got everywhere.

Ignoramus27351 wrote:

I investigated this further. The drive shaft (prop shaft) does not
appear to be loose.

The vibration seems to be related to a gear. If I drive wnd watch RPM,
at around 35 MPH, the vibration starts as soon as the RPM drops,
indicating a gear change. Again, it only appears when I push on gas,
and seems to be further limited to that gear.

Oh OH! That is NOT a good symptom. It may be a combination of
gear and speed, but if it really is only in one gear, it could mean
transmission trouble.

Jon

Jon Elson fired this volley in
:

it could mean
transmission trouble.


Really?
G
(not making fun of you, Jon. It's just that the idea was ridiculed not 24
hours ago.)

Lloyd

On 2013-10-09, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
Jon Elson fired this volley in
:

it could mean
transmission trouble.


Really?
G
(not making fun of you, Jon. It's just that the idea was ridiculed not 24
hours ago.)

Lloyd

Just making sure, I think that I did not ridicule anything. I
hope. Anyway, this pick-up towed a lot of stuff. So, while I would
hate the idea of transmission trouble, it could mean that. I will have
one mbile mechanic I trust stop by tomorrow, I will see what he says.

i

Ignoramus27351 fired this volley in
:

I think that I did not ridicule anything.

No, you didn't, Ig.

High-rate stumbling in one gear is a pretty sure sign of a clutch failing
(rapidly, at this point). It's not _always_ expensive, but almost always
involves a 'pro'.


Lloyd

On 09/10/13 23:10, Lloyd E. Sponenburgh wrote:
Ignoramus27351 fired this volley in
:

I think that I did not ridicule anything.
No, you didn't, Ig.

High-rate stumbling in one gear is a pretty sure sign of a clutch failing
(rapidly, at this point). It's not _always_ expensive, but almost always
involves a 'pro'.


Lloyd
Your clutch comment reminded me of a mate in high school in Wichita
around 1982 and he had an odd vibration on his pick-up and when the
school shop looked at it they found the flywheel had a crack around the
central hub about 3/4 of the way round by the time they pulled it.

On 10/8/2013 7:38 AM, wrote:
On Tue, 08 Oct 2013 05:38:36 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Ignoramus3720 fired this volley in
:

I have a problem that I noticed with my pick-up truck.

The problem is that at certain speeds, such as 40-45 MPH, I feel
vibration if I step on the gas pedal and try to accelerate. If I let
go of the gas pedal, vibration stops even as the truck continues to
drive forward. It has gotten worse lately. I have thought a lot on
what could cause it. It does not seem to be related to the engine
RPM. I watch the RPM vary and the vibration does not vary with it.

What could it be?

i

In addition to the suggestions about U-joints and trannies (but not
tires), It could be a torque/speed problem related to the engine
performance. It might be missing at a certain torque and speed AND
vehicle speed range.

I lean more toward it's being a tranny problem.

When's the last time you completely drained, flushed, and re-filled the
transmission?

Lloyd
We are talking about the old horses vs zebras vs unicorns thing here
again.

Check for horses first. For all it takes to pull a driveshaft, just
pop it out and chech each joint for play/stiffness. Mabee half an
hour's work on a bad day? And if the joints are bad, you have 1/4 of
the work done already.

If I ever go this far, I'm changing them - no matter what. I still
believe in the clunk clunk sound forward to reverse for u-joints going
out. Don't know if his truck has a carrier bearing, though I doubt it
would contribute to the vibration.

I lean strongly to tires or wheels. Have a Freightliner that always had
a very noticeable vibration at 46-47 MPH, gone by 48. It was much more
obvious on acceleration, not so much on deceleration. Had to change
those tires 2 months ago, made a good deal on Michelins - no more
vibration. Go figure! YMMV.

--


___________________________________

Keep the whole world singing . . .
Dan G
remove the seven

On Wed, 09 Oct 2013 07:01:18 -0700, Larry Jaques
wrote:

On Wed, 09 Oct 2013 20:37:37 +0800, Glenn B
wrote:

On 9/10/2013 4:39 PM, wrote:
On Monday, October 7, 2013 8:08:54 PM UTC-6, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck. The problem is that at certain speeds, such as 40-45 MPH, I feel vibration if I step on the gas pedal and try to accelerate. If I let go of the gas pedal, vibration stops even as the truck continues to drive forward. It has gotten worse lately. I have thought a lot on what could cause it. It does not seem to be related to the engine RPM. I watch the RPM vary and the vibration does not vary with it. What could it be? i

Worn suspension arm bushings caused that in my case, the upper suspension arm bonded bushings had deteriorated to the point where there was only shreds of rubber left. The lowers still had the rubber but the bonding to the inner sleeve was gone. I had another vehicle that still had the original factory tie rod ends, these were also bonded rubber and had gone away. Only rattled at certain speeds and really didn't affect steering, somehow.

Amazing. It should have been wandering all over the road after you
hit even a slight bump.


The parts for these replacements were pretty cheap, had to have a heavy press to replace the bushings. Have had to do this now on several vehicles since I tend to run them until they go to the junkyard. Upper bushings are hard to see on a lot of vehicles, hard to get to, too. Bum ball joints will do this, also, but you usually get a vague drifting feel with the steering when that happens. So check your suspension. Only real way I know of is to detach the upper ball joint, get the spring out and see if there's play on arms or ball joints.
Now that I know how, I can usually do both ball joints and bushings on a Sat. Don't go for super-cheap suspension parts or you'll get to do it again quite soon.

Amen to that.


I've had regular Hooke's u-joints go bad with the needles rusted out and gone, never really had any vibration at speed but had a loud clunk when shifting into reverse, this was on an old IH Scout with a three-speed manual and 4WD. Never really caught on until I downshifted on the highway and the stubs broke off on the cross on the front joint. Very noisy. Was my dad's truck when I was a teen and he plowed all winter with it. Didn't get much maintenance in sub-zero. You should be able to check for u-joint play by jacking up a rear wheel and twisting the drive shaft back and forth by hand.

I heard a Mexi-mobile (some funky old chebby) take off from a parking
lot once. EEK-OOK-EEK-OOK-EEK-OOK from zero to 15mph or so. Must have
driven the driver crazy. It was a pole-vaulting event waiting to
happen. When front u-joints let go, it can make for spectacular
crashes on the freeway.

A highschool classmate had a big-block '67 Chevy that he used to drive
pretty hard - Tearing down the street behind the school and
speedshifting, he took out the front U-joint and poked the driveshaft
right through the diff into the gas-tank - lifting the rear bumper a
few feet in the process and tearing a furrow in the asphault.

I had a truck's rear u-joint go while I was following it once. The
center flew out and hit my windshield right between my eyes. Luckily,
it was spinning beneficially to the slant of the windshield, so my
F-150 glass only got a shearing scratch there, no puncture. Most of
it polished out. I was -really- lucky that day. A truck cross through
the forehead would have kinda hurt. I avoided the drive shaft which
the truck jumped over because I was in the next lane over by that
time. Talk about adrenaline shakes...


Had the rear U-Joint let go on the AeroScare on the way from Kitchener
to Winnipeg, via Michigan. I had the u-joint replaced by a shop while
I was out of the country in Burkina Faso for a month, knowing I had
the winnipeg trip coming up as soon as I got home, taking my daughter
to University. The mechanic who installed it didn't get the retainer
clip in right and it threw a cup just east of Flint, friday of the
Labour Day weekend. No tools in the truck - no shop able to do the
job - changed it laying on my back under the truck with a combination
of borrowed tools and a vice and hammer I bought at the parts store
where I bought the U-Joint.

I've also see vibration checked for by putting the vehicle on a lift with the wheels free and running it up to speed with a mechanic looking underneath for drivetrain vibration. It's a last resort, very dangerous, stay clear because rocks can come flying out of the tire treads. If no vibration that way, it's got to be suspension or front wheel bearings.

Stan



.......... or a front tyre issue (I just had one!)

I thought I had a wheel bearing problem in front RHS. Felt ok by hand
when jacked up but made noise at, and varied with speed. I got a
puncture in the RHF & the noise disappeared when the spare was fitted to
the RHF. Tyre looks ok, seems to run true & is balanced. Beats me why
its noisy. I've put it on the rear and don't notice any noise now.

Prolly ply sep in the tread area. They're easier to diagnose in the
sidewall, where you can physically see them through the thinner rubber
layer.

On Wed, 09 Oct 2013 14:28:45 -0500, Jon Elson
wrote:

Ignoramus27351 wrote:

I investigated this further. The drive shaft (prop shaft) does not
appear to be loose.

The vibration seems to be related to a gear. If I drive wnd watch RPM,
at around 35 MPH, the vibration starts as soon as the RPM drops,
indicating a gear change. Again, it only appears when I push on gas,
and seems to be further limited to that gear.

Oh OH! That is NOT a good symptom. It may be a combination of
gear and speed, but if it really is only in one gear, it could mean
transmission trouble.

Jon
If it seams like it might be transmission related, get a can of BG
ATC. If it is a sticky or floating valve in the trans it could quite
possibly solve the problem and it definitely won't hurt. It won't fix
a mechanical problem - but can solve accumulator and valve related
issues, as well as some friction material issues. If it makes a
difference you KNOW it is transmission related and you can decide how
much you are willing to do to the tranny. If it doesn't help, it's
only about 8 bucks.

On Wed, 09 Oct 2013 23:03:36 -0400, wrote:

On Wed, 09 Oct 2013 07:01:18 -0700, Larry Jaques
wrote:

On Wed, 09 Oct 2013 20:37:37 +0800, Glenn B
wrote:

On 9/10/2013 4:39 PM, wrote:
On Monday, October 7, 2013 8:08:54 PM UTC-6, Ignoramus3720 wrote:
I have a problem that I noticed with my pick-up truck. The problem is that at certain speeds, such as 40-45 MPH, I feel vibration if I step on the gas pedal and try to accelerate. If I let go of the gas pedal, vibration stops even as the truck continues to drive forward. It has gotten worse lately. I have thought a lot on what could cause it. It does not seem to be related to the engine RPM. I watch the RPM vary and the vibration does not vary with it. What could it be? i

Worn suspension arm bushings caused that in my case, the upper suspension arm bonded bushings had deteriorated to the point where there was only shreds of rubber left. The lowers still had the rubber but the bonding to the inner sleeve was gone. I had another vehicle that still had the original factory tie rod ends, these were also bonded rubber and had gone away. Only rattled at certain speeds and really didn't affect steering, somehow.

Amazing. It should have been wandering all over the road after you
hit even a slight bump.


The parts for these replacements were pretty cheap, had to have a heavy press to replace the bushings. Have had to do this now on several vehicles since I tend to run them until they go to the junkyard. Upper bushings are hard to see on a lot of vehicles, hard to get to, too. Bum ball joints will do this, also, but you usually get a vague drifting feel with the steering when that happens. So check your suspension. Only real way I know of is to detach the upper ball joint, get the spring out and see if there's play on arms or ball joints.
Now that I know how, I can usually do both ball joints and bushings on a Sat. Don't go for super-cheap suspension parts or you'll get to do it again quite soon.

Amen to that.


I've had regular Hooke's u-joints go bad with the needles rusted out and gone, never really had any vibration at speed but had a loud clunk when shifting into reverse, this was on an old IH Scout with a three-speed manual and 4WD. Never really caught on until I downshifted on the highway and the stubs broke off on the cross on the front joint. Very noisy. Was my dad's truck when I was a teen and he plowed all winter with it. Didn't get much maintenance in sub-zero. You should be able to check for u-joint play by jacking up a rear wheel and twisting the drive shaft back and forth by hand.

I heard a Mexi-mobile (some funky old chebby) take off from a parking
lot once. EEK-OOK-EEK-OOK-EEK-OOK from zero to 15mph or so. Must have
driven the driver crazy. It was a pole-vaulting event waiting to
happen. When front u-joints let go, it can make for spectacular
crashes on the freeway.

A highschool classmate had a big-block '67 Chevy that he used to drive
pretty hard - Tearing down the street behind the school and
speedshifting, he took out the front U-joint and poked the driveshaft
right through the diff into the gas-tank - lifting the rear bumper a
few feet in the process and tearing a furrow in the asphault.

My buddy with the '67 Goat went through driveshafts, trannies, diff
nuts, and axles like -popcorn-, but he never went pole vaulting. I
used to kid him about all the money he threw away by being so
aggressive behind the wheel.

When I stood on my Javelin, the whole rear end dropped 7 inches as it
wrapped the springs around the axle, but it then shot like an arrow.
The close ratio Borg tranny was hard to keep up with behind the
slightly built 390. (circa 400hp and 450ft#) I'm really surprised I
never lost a u-joint.


I had a truck's rear u-joint go while I was following it once. The
center flew out and hit my windshield right between my eyes. Luckily,
it was spinning beneficially to the slant of the windshield, so my
F-150 glass only got a shearing scratch there, no puncture. Most of
it polished out. I was -really- lucky that day. A truck cross through
the forehead would have kinda hurt. I avoided the drive shaft which
the truck jumped over because I was in the next lane over by that
time. Talk about adrenaline shakes...


Had the rear U-Joint let go on the AeroScare on the way from Kitchener
to Winnipeg, via Michigan. I had the u-joint replaced by a shop while
I was out of the country in Burkina Faso for a month, knowing I had
the winnipeg trip coming up as soon as I got home, taking my daughter
to University. The mechanic who installed it didn't get the retainer
clip in right and it threw a cup just east of Flint, friday of the
Labour Day weekend. No tools in the truck - no shop able to do the
job - changed it laying on my back under the truck with a combination
of borrowed tools and a vice and hammer I bought at the parts store
where I bought the U-Joint.

I hope you asked for and got a full refund from the jerk who did that
to you. "Refund or lawsuit, what'll it be, sir?" big grin

--
Win first, Fight later.

--martial principle of the Samurai