Do a search, there are enough oil threads to keep you busy for a long time.
there are also as many opinions on which oil to use and how long. opinions are just opinions, get the facts.

synthetics flow and protect better, and can be left in longer. just because the oil gets dark doesn`t mean it needs to be changed. send a sample to a lab. and you will get a readout of what is going on in the engine.

not all synthetics are created equal, and some are not true synthetics.

Iam not a dealer or salesman and not connected with any oil co. but I use Amsoil 15w40 in my 85 300D along with the full flow bypass filter along with the stock filter. I just changed the engine over to it now that it is broken in. I noticed it ran smoother, and the temp seems to not run as hot.
I also changed the trans at 331000 miles to syn. it shifts smoother, and does not leak.

There is that fear it will cause leaks on a high milage engine. I have not had that problem.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works