I switched to synthetic some where over 300000, don`t remember exactly. I do know the engine ran so much smoother. I may have had a few drips of oil before the change, but changing to synthetic didn`t increase the leaks.

I did have the timing chain break at 330940 miles, but was unrelated to the oil.

as far as the synthetic loosening up gunk in the engine, isn`t the filter there to catch all this gink. if the oil has been changed on a regular basis, there shouldn`t be a lot of gunk.

the syntheric I use is Amsoil 15/40 Marine Diesel, and I use the Amsoil full flow by-pass filters.

my 2¢ worth.

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