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Ignoramus28705

On 2012-03-04, wrote:
On Sat, 03 Mar 2012 22:28:29 -0600, Ignoramus20398
wrote:

On 2012-03-04, Pete C. wrote:

Ignoramus20398 wrote:

On 2012-03-03, Karl Townsend wrote:
On Fri, 02 Mar 2012 21:28:21 -0600, Ignoramus22470
wrote:

On 2012-03-02, Karl Townsend wrote:
On Thu, 01 Mar 2012 23:03:30 -0600, Ignoramus6107
wrote:

I have been practicing and driving my semi tractor almost every day
recently. Not much time every day, but I usually manage to find at
least some time every day. At my age and after 17 years of driving
auto transmission, the skills to drive a truck with an unsynchronized
manual transmission do not come easily, but I am making progress. I
can now shift up and down, and by now, it works well most of the time.

I will soon try to pass a theoretical exam to get a CDL learner's
permit.

i

You're learning at a better age than myself. I started driving
truckloads of wheat to the elevator at 14. Dad told me to never go on
the highway. Of course, I ignored that. I forgot to down shift at the
top of pleasant grove hill. When the brakes wore out, I tried to down
shift and missed it. That old truck was doing 80 at the bottom of the
hill. I was lucky to see 15. But, I've never forgot to down shift
again.

I have found a golden guy, an honest mobile mechanic, I will have him
check my brakes out.

i

Iggy, just in case you don't alread know, NEVER go down a hill in a
gear higher than you go up it. Downshift at the top. No matter how
good the brakes are, it won't stop 80,000 lbs. I just told you how i
learned this.

Karl

Karl, I am aware of this, yes. I think that proper brakes are enough
to slow down downhill and to switch to low gear, but I am aware of the
brake fade phenomenon.

The problem is not the brake fade, the problem is if you do not do your
downshift before you go over the crest of the hill, you have very poor
odds of being able to successfully complete the downshift on the
downgrade. What happens is you get it out of gear and then you are
unable to get it into the lower gear and often you can't get it back
into the previous gear as well. This leaves you on a downgrade in
neutral with *no* engine braking at all and your service brakes won't do
the job. It's runaway truck ramp time if you are lucky enough to find
one.

OK, I will bite, why would the service brakes not do the job and stop
the truck, at least once?

i
They MIGHT - under ideal conditions - if applied and held. Let off
once and re-apply and all bets are off. Are you willing to take the
chance????? Engine compression braking - and better yet a Jake or
exhaust brake, are the much safer "bet".

I do not think that I have a Jake brake. Thanks. What you say makes
sense.

i