Does synthetic oil burn really clean?

[ron in sc]

I have a 1992 Mercedes 300 TE with 140K miles on it. It uses about 1 quart of Mobil 1 20W50 about every 1750 miles, with half the miles highway and the other half city.

No oil leaks, no oil in coolant, no blue smoke on startup or while running, no oil in air filter or in intake manifold, and spark plugs look as they should.

So I'm wondering if synthetic oil burns really clean.

It is a known issue that the motors in these cars, specificaly the M103, have valve stem seals that need to be replaced periodically so that may be part of the reason I'm using oil.

I should also mention I've used the same weight and brand of oil since the car had 60K miles on it.

 

[mcrn]

As far as I know Mobil does not make Mobil 1 in 20W50. Did you mean 15W50?

 

[bmwtechguy]

I had the same question and I'm sure hoping he's not paying to put the 20W-50 M1 motorcycle oil in this oil-consuming engine.

I'm guessing that synthetic oil, if being consumed, could "burn" cleaner, but not sure how much difference it would make overall.

I have found that sometimes synthetic oil gets consumed faster than same viscosity non-syn oil in some engines, and that some brands of synthetic get consumed at a faster rate than others, all other things being equal.

 

[ron in sc]

Quote:
Did you mean 15W50?


Yes.

 

[rg200amp]

How many miles are on the car now?
How much oil does it consume?

 

[eljefino]

FWIW, mazda recommends against syn in some of their RX7 rotary engines because the flash point is so high it doesn't burn when it's supposed to, by design of the rotary engine.

 

[Audi Junkie]

Why are you putting synth oil, that synth oil, in that engine which consumes oil so fast??? Are you leaking or burning? If you just want to know about clean burning synth, Jag did a bunch of tests on this subject. Maybe in the Euro oils section. Valvoline SynPower looked good and is good in that 20w-50 grade. Dino 15w-40 would be a better bet, imo.

 

[CharBaby]

Originally Posted By: rg200amp
How many miles are on the car now?
How much oil does it consume?

I have a 1992 Mercedes 300 TE with 140K miles on it. It uses about 1 quart of Mobil 1 20W50 about every 1750 miles, with half the miles highway and the other half city.quote]