oil selection

[fredfast]

97 LaSabre 104000 miles.
Have had numerous problems all the usual ones. The car has always used 1 quart of oil approx 2k miles, dealer showed me some literature that stated that was normal.
Is it a good/bad idea to switch to 10w40 ?
Thanks.

[auto trainy]

Bad Idea,I would stick with or switch to a good blend of 10w30 and stay away from 10w40 GM engines dont like it and I remember something a while back where GM said not to use it,but like I said it was a while ago.

[happydog500]

My 97 has 130,000. Everything was done by the book (Dad's car) oil every 3000, etc.... Most miles are highway, overdrive miles. It uses about a quart every 1,500 (Pisses me off).
A friend's car just like mine with 150,000 "doesn't use a drop" in 3,000.

[tman]

Use 10W30 or 5W30, both are just fine. If your low outside temperature rarelt hits the teens, then 10W30 is fine. It your in lower temperatures, go with 5W30, because it is thinner.

[imidazol97]

The 10w-40 has certain chemicals in the makeup of the molecules that change shape with temperature that caused deposites on the rings--long ago. That may still be true; it may not be.

A little oil is cheap. When it hits 1 quart in 800 miles then start looking for alternative methods.

The oils for motors with higher miles on them help. A car guy said they soften seals and reduce lose in that method helping consumption. I had heard previously then tended to be high on the rating helping act like a higher number oil. E.g., 10w-30 might be more like 12w-35, thus helping consumption.

A mechanic friend has a 97 LeSabre with something like 250K. He uses 20W-50 in it; probably 10-40 in winter. That might be your final choice on oil.

[Loekee75]

My 92' Park Ave has 156,000k on it, was used a travel vehicle, and only uses roughly half a quart in 3,000 miles...does that sound too good to be true or are my eyes deceiving me?

[HotZ28]

Originally Posted by Loekee75

My 92' Park Ave has 156,000k on it, was used a travel vehicle, and only uses roughly half a quart in 3,000 miles...does that sound too good to be true or are my eyes deceiving me?

This is not unusual for some engines to use a quart in 2K, while others can go 5K without using hardly any. I have always used Mobil-1 and change it at 8K intervals. My 92 Ultra has 175K on it and will be no more than a quart low when I change it. I just checked it today, with over 6K on it since last change and it is less than 1/2 quart low.
One thing I learned a long time ago while working with GM Dealers, is that oil consumption is directly proportional to how an engine is broken-in, during the first 1500 miles. Some people baby them, during the initial break in period, (bad) and others drive them like they would everyday (good)! The ones that are driven hard always seem to seal the cylinders sooner and therefore consume less oil throughout their life. You want your rings to expand and contract a lot during the first 1500 miles. That means, not driving the first 1500 miles at a steady speed on the highway, but to make short trips and accelerate and decelerate as much as possible (expanding & contracting the rings).

As for oil types, of course I would have to recommend Mobil-1 10W30 "extended life formula" (pure synthetic). It sure does the job for me; however, it is not a cure for engine already consuming oil!

[fredfast]

Thanks to all for the responses. I guess what seems to bother me is ,I change oil @ 5k mls. At the rate it uses oil (2 qts in 4k mls) almost 1/2 the oil has lesss than 5k on it at change time.
Having said that, as was stated in the forum oil is cheap,so I am staying with GM guide lines.
Thanks again.

[Hapynzap]

I just checked my oil, not quite a half quart low at 2800 miles. Im running regular Mobil 1 till 5000. Should make it till then so no need to top it off.

[tman]

Just to state a fact here:

My 94 Park Avenue with 152000 miles uses absolutely NO oil. It's had havoline 10W30 in it as long as we've had it(70,000 miles it was bought at)

It's not uncommon for these engines to use none. My only tips are never ever run it hard until the temp guage reads 195. It only takes one time to mess it up

[imidazol97]

Oil consumption can vary depending on how a car is driven. If you have a car with miles on it and it's driven in low speed driving for shorter periods it may not burn away contaminants that end up in the oil. That replaces some of the lost oil over a couple thousand miles and makes it appear the car uses less.

Take the car that has oil with 3000 miles on an hour long interstate drive and check the oil when you get home. The higher heat will burn away the contaminants which ended up in the crankcase and people will assume their car uses oil all of a sudden when it's driven on the interstate or at least at higher speeds over a period of time. In reality the contaminants got burned away.

[Hapynzap]

Any oil that gets somewhat vaporized can be sucked out thru the pcv valve. I've noticed that synthetic oils tend to go down faster than dino oil. I'm not complaining at one quart per 5000 miles though.

[happydog500]

Originally Posted by imidazol97

The 10w-40 has certain chemicals in the makeup of the molecules that change shape with temperature that caused deposits on the rings--long ago.

Wouldn't deposits on the rings help seal the rings? With my oil consumption, I pray for something to put on the rings that might help seal. Chris.

[imidazol97]

Originally Posted by happydog500

Wouldn't deposits on the rings help seal the rings? With my oil consumption, I pray for something to put on the rings that might help seal. Chris.

Those deposits gunk up the rings (oil rings) and keep them from moving in and out freely with the wall of the cylinder to keep the oil from being left in the combustion chamber to burn away during the explosion.

[tman]

Originally Posted by imidazol97

Oil consumption can vary depending on how a car is driven. If you have a car with miles on it and it's driven in low speed driving for shorter periods it may not burn away contaminants that end up in the oil. That replaces some of the lost oil over a couple thousand miles and makes it appear the car uses less.

Take the car that has oil with 3000 miles on an hour long interstate drive and check the oil when you get home. The higher heat will burn away the contaminants which ended up in the crankcase and people will assume their car uses oil all of a sudden when it's driven on the interstate or at least at higher speeds over a period of time. In reality the contaminants got burned away.

If you were responding to me, I'll have to contest what you've said. My buick recieves trips around town and on the interstate frequently. It burns nothing but fuel and tires I'll completely agree with you that this CAN indeed be the case for some cars, but you CANNOT make this generalization for ALL of them.