Well first the engine rpm and what gear the trans was in will be in memory
if a catastrophic engine failure occurs, that stops the engine from running.
Normally the engine would be inspected internally to determine the cause and
extent of the failure and of course was the engine subject to abuse or lack
LOL, nothing happenned !! I am just curious , sorry if I have disapointed
some of our readers .
I was on Bobistheoilguy.com the other day and they had a discussion about
engine oil and warranty.Many opinion, very few fact. So I decide to come
where I will find peoples working for GM and knowing the procedures that a
dealership MUST follow before they give the ok to fix the engine.
Question like are they going to send a sample of the oil for an analysis,
are they going to argue if you change your oil at home ? ( i understand that
we should show the billof sale )
Some peoples prefer to use some oil not listed in the manual, oil result are
then monitored by analysis and many time the result is better than what they
Only that , no suspense here ;-)
Oh, ok. I thought there might be some interesting
story behind your question.
A lot will depend on the circumstances, but I can safely say
that 95% of the time...the dealership will go with the
customer. There has to be some serious signs of neglect
or abuse, and even then....if it can't really be proven, the
benefit of the doubt is given to the customer.
> Question like are they going to send a sample of the oil for an
If there is some argument about maintenance, yes, they might
want an oil sample. But frankly....I'm not sure what good
an oil sample will do. If you have some sort of catastrophic
failure, there will be all sorts of stuff in the oil sample...so what!
Oil changes at home are no problem, but you should keep
a log book. They aren't even really looking for oil and filter
receipts, but that would help. If you show them a well kept
log book of what you do...that will suffice.
A lot of people will disagree with me...but as far as I'm concerned,
oil is oil...it will make no difference what oil you use....if you kept
to an oil change schedule of 3000 miles/3 months...you can use
whatever oil you want (as long as it meets currents specs) and there
could be no argument from GM about that. What do you think
we use in the dealerships? It's just bulk 5/30 or 10/30. Again,
as far as I'm concerned, there is no difference running either one
of these...it will make no difference to the motor. There are some
exceptions....one I can think of involves the Northstar motor. The
early motors that used bucket style lash adjusters are supposed to
run 10/30 oil as this style of cam lobe and lash adjuster need a
slightly thicker film of oil, the new engines that use roller rockers
can use 5/30 oil. Other then that, I can't think of any engine that
you could point to and say "that blew up because the guy was
running 10/30 as opposed to 5/30". And I know that many
of the lube kids just throw 5/30 in everything anyway.
I've successfully used any oil that I can get my hands on
in my own beater car and I've never had any engine failures.
I'll even throw in a quart or two of 15/40 diesel oil if some
spare stuff is kicking around. It makes no difference. I try
to avoid using that in the winter, but even then...it just
cranks a bit slower....still starts and runs fine.
Talk to any engine rebuilder and once you take apart an engine it is very
obvious if the owner has been regularly changing oil or not. I have never
myself sent in a warranty claim for a blown engine in a new vehicle nor have
I ever heard of anyone who has done so, but I would guess what happens
is that if you were the type that never changed your oil from the factory,
when the engine was sent back to GM for analysis, as soon as they got it
open they would be calling you and denying the claim. It is very unlikely
most dealership service departments would be able to make a determination
in any case, as the factory wants the blown engine sent back intact so
they can determine if the failure is a design problem or not, the dealership
isn't going to be allowed to get far enough into the engine to be able to
make a determination of improper engine oil changing or not.
This is only true if the engine in question is still "on restriction".
GM has a policy where a new engine is "on restriction" for about a
year. Any major internal problems, and the engine is sent back to
the factory intact. As soon as the engines come off this restriction
period, we open them up and make the determination as to whether
it will be warranty or not. If it's a particularly sticky situation, the
DSM (district service manager) will get involved and help make
the call. But I've never seen warranty denied after the fact. Once
the determination is made....the new engine goes in, the old engine
"may" get recalled or it may not. It will sit around the dealership
for a period of 3 months and if it hasn't been recalled by the factory,
it gets tossed out. Or if someone is particularly sharp and wants
parts off of it, it will mysteriously disappear....(grin)
I think if I worked in a dealership, all those tossed out parts
would mysteriously disappear. Right under the tannu cover of my pick
up. Then what I didn't need would magically show up at the metal yards.
Well...in theory we are supposed to destroy warrantied
parts. But it doesn't happen much these days. If there
is something I want....I keep it in my bay until the waiting
period is over, check with the warranty guy in parts to
confirm this, and then the engine might disappear.
That's what I would do. I would never take anything that wasn't
kosher. I have a few dealer tech buddies, so I know what your talking
about. They would never take an item they didn't have full permission to
I just have a thing about tossing metal parts in to the trash. I
would rather go thru the effort of cleaning them (such as removing steel
from aluminum), and recycling them for a wee bit of gain. Metal yards
around here will give you on average$20 per ton more for cleaned engines
(bare blocks and heads) then they will for a ton of short iron.
I believe it is possible to see how much oil life is remaining since it was
last reset, but there is no history maintained beyond that (except for
problems which cause diagnostic trouble codes to set)..
Robert Hancock Saskatoon, SK, Canada
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