Would you like to put money on that, Willy. I still take Paypal.
I'm a GM dealership tech with the online Service Manuals and
the Owner Manuals at my disposal.
Doesn't matter if it's a 2006-2007 model. Still says the same
Very interesting post.
If there is an engine failure within in GM's warranty period, do they ever
ask for verification of oil changes in a timely manner? Timely manner being
the interval listed in the owners manual.
It depends. If nothing really stands out to the tech when tearing
the engine down, then it just gets repaired. If the engine is
seized, and when we drain the oil, all that comes out is jelly,
then yes, they may ask for maintenance records.
This gelled oil problem stands out as a problem for a number of
Paraffinic oils do not normally gel under heat alone. The additives can "go
but the basic oil molecules are relatively stable. They can gel if water is
into the equation, or if polymerization occurs *, or if additives give up
the ghost, or
if crosslinking via salts occurs.
Synthetics are not necessarily immune to this either.
If oxygen (read it the same as "air") gets into hydrocarbons or synthetic
heating is applied, then the whole chemistry changes. Acid numbers
Viscosity increases. Density increases. Color goes to brown or black.
plus the decomposition of additives, are the main two causes of varnishing
of engine parts
If an engine has small oil passages, the problem is aggravated.
I tend to think that the real problem with gelled or sludged oil is well
defined, but that
the ultimate repositories of this knowledge are protecting the information.
IF you abuse your car, then - I agree - you have no comeback. If however
of design and operation are such that failures occur suddenly and without
then the manufacturer needs to belly up to the apology counter.
Maybe someday we will know the facts in these cases.
For whatever reason, GM engines have not had any issues
with "sludging" that I've ever seen. Any gelled oil in their engines
has always been due to lack of maintenance on the customers
part. Doesn't mean that some of them don't get warrantied, GM
tends to give the customer the benefit of the doubt.
I understand that. But that's a different subject. There seems to be
an increasing amount of oil related problems with many different
manufacturers, but for the moment, GM seems to be untouched
Hey, you know me....I think that the Gen II 3800 was a sorry
piece of engineering in more ways then just the intake plenum
failures. Too bad, really. The basic engine is fantastic.
IMO you are right on target in everything you have said. AFAIK, GM
has not had the oil problems that other manufacturers, including Toyota,
Volkswagen, Chrysler, etc have had.
None of these cars run vastly higher temperatures than the others, so it
is not just a temperature problem. Nor is it a shootout between synthetic
versus dino oils.
I believe that most of the problem is due to disastrous engineering, and
a little of it may be due to poor maintenance by the owner.
The only exception being certain Saabs, one of which just bit my friend
very hard in the wallet. Saab issued several TSBs to update the PCV
system but never notified owners and went through multiple fixes before
finally getting something which seems to work. People who were having
their cars properly maintained, but by independents, often missed
getting the updates. My friends 9-5 engine is now complete toast due to
oil problems which were not caused by improper maintenance.
The mainline US GM brands seems to have so far avoided the oil sludge
Do you know what oil he used, and what change interval he observed?
I am curious, because there is a lot of speculation that (1) synthetics
have held up better, or (2) shorter change intervals would have solved the
problem, or (3) the PCV system is a major cause (if not THE cause) of these
problems and it is a design or implementation problem.
Lots of buck passing...
I do not understand why people consider a pushrod
engine "ancient" or somehow less of an engine.
OHC engines have been around since at least the
1930's. It's not new technology.
Would you rather have the OHC engines that come
in Ford trucks, the ones where you have to lift the
body or cab off the frame in order to even work on
the silly engine?
The Chev small block engines are a fantastic engine!
Pushrods and all. And very easy to work on.
Sorry, Ian, making a joke. Perhaps there's something about och engines that
encourages sludging. I agree with your assessment of the engines. Why make
an expensive, heavy OHC when simple, reliable OHVs are getting the job done.
My 2003 LeSabre with a 3800 V6 has the engine oil monitor but he manual
still states to change oil at 3K mile intervals.
My 2006 Lucerne with the Northstar V8 manual refers to using the oil monitor
to indicate when an oil change is required or one year if the monitor does
not indicate time for a change.
I'm picking up a 2007 Lucerne next week, this one with the V6. For this
vehicle do I use the 3K mile interval or rely on the oil monitoring system.
For everyone? IIRC, the 3000 miles is only for severe use. I've only ever
used the monitor for my LeSabre and changes are at about 7500 miles. My
commute to work is 26 miles and I don't do much city driving at all. It all
you ever do is go to the grocery store a mile away, the 3k may be correct.
Of course, the monitor should tell you that.
You are right about two oil maintenance levels, 3K and 7.5K. My point was
that in the 2003 LeSabre manual there is no mention of using the oil
monitoring system for determining change intervals.
For the LeSabre I consider the driving conditions as close to severe. Lots
of 20 MPH/stop~go driving, not in cold weather (central Florida). Even
under these conditions the oil monitoring system has never been below 60% at
3K miles of actual driving.
My 2006 Lucerne manual doesn't say anything but use the oil monitoring
system to determine oil changes.
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