1995 SL 1 oil consumption
 

I know there are many threads on this subject but I wanted to see if there was any new advice.
My 95 SL 1 has 65000 miles on it. When driven at interstate speeds about 2 quarts in 300 miles. Since then, just driven around town. We did the Berryman B-12 Chemtool thing and now use one quart in 500 miles of city driving. We usually don't drive over 2000 RPMs. I would like to get it down to a quart in 1000 miles but not sure if just doing another Chemtool treatment would do the job. We use Mobil One full synthetic 10-30. I would love to rebuild the engine but it just doesn't make sense financially. The car is very nice and I want to keep it. If I have to keep adding oil I will but I know it's not doing my emissions any good and probably ruining my CAT. Replaced the EGR valve already.

A set of rings and gaskets will probably stop the oil consumption.

1995 sl1 oil consumption
 

Wouldn't they have to take the engine out to do that? Any idea of the cost?

Most independent shops would do it with the block still in the car. Remove the head and pan, replace the rings and put it back together. No idea on cost where you live, call around.

Is the problem in the rings or in the pistons? I've never taken an engine apart, but I've read something about some kind of an oil return groove that was a defect in these engines.

These engines came with rings that gum up very quickly and stick in the pistons. Strangely cars that got proper oil changes never had a problem. Not really strange is it? I am driving a Saturn with a different engine than your car but it has 272,000 miles and has never been apart and uses no oil between changes. It is amazing that they don’t teach this in school, pay me now or pay me later.

I will try to find a local shop to replace rings and gaskets. In the meantime, I'll do another B-12 Chemtool treatment. However, I've found a product that has been around for a long time. It's called Kreen gas and oil treatment. Made by a company called Kano Labs located in Nashville, TN. Anyone had any experience with this product?

Jumping in here....IMHO it's the pistons, according to my research, the drain back holes in the pistons were too small........they did a revision but there is no clear line of demarcation. My guess is the revised pistons made it into different batches of production. Goldie my 99 uses no oil, greenie used oil, it was a 97. Whitey the 2001 uses no oil. Red is a 99, she uses oil....but I did a top end soak, put all pistons at same level, filled cylinders w/a solvent. (mystery solvent!! found it in my hangar when I bought it, smelled like lacquer thinner and didn't evaporate very fast??) I suggested it to my daughter and she agreed to try it!
Let it soak overnight, in the am I put about 4 oz. of MMO into each cylinder let it soak for about 2 hours, hand rotated the engine.
Blew 150# air thru each cylinder at TDC............(oil drain was out)
Put the old plugs back in and fired that muther up..........
Smoked like a banshee........then I steamed her (introduced water into it at WOT) I use just enough water to keep the RPM's around 3500-4000 max, too much and you will stall it.
Installed new plugs.
She reported a significant reduction in consumption but we don't have actual numbers, she knows she's adding LESS oil.
I explained to her the risk/reward ratio BEFORE I did it and she agreed...........besides she knew if I messed her engine up I'd just fix it!! (A year earlier I did an in-chassis re-ring on my other daughters Accord after I discovered #4 exhaust valve was toast)

So be advised I knew the risks, could blow head gasket, clog the cat, but Red's got about 130K on her so I figured I'd experiment a bit. I would not recommend this to a non-mechanic, Simply pulling the head and dropping the pan is easy, knock out the pistons (after removing any ridge or gunk) and put on the revised STD. pistons and slap on a rebuilt head, your good for at least 250K miles.Hope this helps, think it over and good luck
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So, as I read it, it could be stuck rings with good pistons or stuck rings with bad pistons or good rings with bad pistons. The only way to know for sure is to do new pistons and rings. Don't know if it's worth the money. I'm pretty old-85- , fixed income and all that junk, and maybe I should just keep adding a quart every 500 miles. ?

Adding oil is the least expensive solution. The cat may die and they can be expensive in a smog inspected state.