On Sat, 27 Mar 2021 03:58:21 +0530, mike
wrote:

On 26-03-2021 20:34 Scott Dorsey wrote:

No, you're not following the guidelines in the service manual.

Now you're just being silly.
Every car ever sold specified the current oil spec as the guidelines.

We've been at this since round about API SC days as I recall (do you?).
As I recall when the emission stuff hit the fan we jumped all the way to SD.

It's been that uphill climb ever since for every vehicle sold in the USA.

I pulled out my shop manual for a 1997 Japanese vehicle and it says on page
LU-1 "API grade SH Energy Conserving if multigrade engine oil or ILSAC
multigrade engine oil SAE 5W30 is the best choice for your vehicle, for good
fuel economy, land good starting in cold weather." On page LU-2 it says to
use 5.4 liters (5.6 US qts) with oil filter change and 4.7 liters (4.2 US
qts) without oil filter change.

It even specifies a "Dry Fill" on page LU-3 of 5.8 liters (6.1 US qts) which
I don't remember if I've seen that in other service manuals (have you?).

Looking in a 2002 German factory manual on page 020-10 under "Maintenance" I
see my own handwritten note to not to use LL-04. On page 020-6 are the
"Maintenance Tables" and here it says to change both the oil & filter for
Table a. Oil Service, and the same for Table b "Inspection I Service" and
Table d "Oil Service" it says in the chart to use 7.5 liters (7.9 US qt) of
5W-30 synthetic oil BMW part no. 07 51 0 017 866 (LL-01).

Because
if your car was made in 1990 then the oil described in the service manual
is no longer being manufactured.

Stop being silly.
It gets better with each designation.
Sometimes it matters. Sometimes it don't.

Is the current oil better or worse than the oil that was originally
specified? It's likely much better. But you don't really know. All
you can do is drive and hope.

Stop it with the silliness.
It don't get worse for motor oil or for oil filters.

Shows how much you know. Today's spec engine oils will eat the
camshaft out of older flat tappet engines in no time if you don't add
a zinc replacement additive of some sort. It will also wipe the babbit
bearings out of the even older engines with direct babbited bearings.

Lots of other instances where current spec lubricants are NOT
recommended for older engines. Same thing with both automatic
transmission fluids and gear lubricants. (and even antifreeze)

There are some cases in which the current oil formulations may be
problematic for older vehicles. 1990 isn't old enough to worry about,
but some people drive vehicles where they might worry.

I don't know why I'm bothering to pull out my manuals just because most of
you pull all your statements out of your own asses instead of the manual.

You made me go back to my trunk to push the talisman aside (to ward off
those tigers) and on page MA-9 it says to use 6-3/8 qt (US measure) with oil
filter and 5-7/8 qt (US measure) without oil filter and in the "Recommended
fluids" column it says "Energy Conserving Oils of API SG asterik 2, asterik
3.

Asterik 2 For further details see Recommended SAE viscosity number (MA-10)
Asterik 3 Energy conserving oils. These oils can be identified by such
labels as EC-I, EC-II, energy conserving, energy saving, improved fuel
economy, etc.

On page MA-10 there is a viscosity chart with the captain of "10W30 is
preferable if the ambient temperature is above -18C (0F). 20W-40 and 20W50
are usable if the ambient temperature is above 10C (50F) for all seasons.

Anyways out of three factory manuals the two Japanese manuals specify oil
without filter and only the German manual specifies the oil with the filter
every time.

I don't know why I bother to dig these up just because most of you pulled
your comments out of your asses which is why you're wrong on all counts.

In the end (given that's where your ideas come from) you can change your oil
and filter on any interval you like but stop making up **** about the
factory specifications please.

Two out of three of my own shop manuals refute everything you people claim.