Using Oil?

[MERCEDES300CE]

Hi,

I have a 90' 300CE, 24v, M104 motor, aprox 180K miles. The question is since I swaped over to synthetic oil I seem to be "using oil", meaning it is not leaking out, or burning it. The antifreeze seems clear, as the head gasket was changed about 60k miles ago. I am going thru about 2 quarts between changes, 3K mile changes.

The mechanic says it is normal to "Use oil between changes". As I have owned the car for several years now and put over 100k miles on it, I find it odd that all of a suden it does this. Should I put Dino oil back in and see if the problem persists or is this in fact "Normal".
Any thoughts are greatly appreciated. Thanks in advance.

[mreid]

Using oil?? How much? How long have been using synthetic. It is not unusual to use oil when changing to synthetic. Don't worry unless it keeps it up for several changes.

well 1 quart per 1500 miles is acceptable. but i dont like it myself even though its normal.

[MERCEDES300CE]

Hi,

Thanks for your reply's.

Prior to the synthetic the car used no oil between changes, maybe coincedence, not sure.

This will be my third oil change, since the swap to synthetic, so about 8K miles. The first change was to Mobile 1 10-30, then the dealer recomended I go to 15-50, stating the 10-30 was too thin. So the second change was to the 15-50. Now I am debating on wether or not I should continue with the synthetic or change the weight to 0-40.

Any input is greatly appreciated. Thanks,

[kowached]

Synthetics leave a thinner film of oil on the friction surfaces of your engine, so if your engine has been running on mineral oil for many thousands of miles before it is switched to synthetic its very possible that it will sneak by your piston rings. That's one of the drawbacks to synthetics if you don't start using it on a young engine (before 60,000miles or so), but you can't get the high temperature protection and low temperature fluidity for free. I'd suggest switching back to a high grade mineral oil, or maybe even a synthetic blend. It might not be too late to use it in your trans and rear axle.