(24-03-2012, 10:39 PM)j90xxx Wrote: From what I remember from my days working in the automotive oil industry, an engine that has been using fully synthetic from new should ALWAYS be run on fully synthetic. If it has been running on mineral or semi synthetic, then fully synthetic should NOT be used.
Will do some homework to confirm or deny, but sure that is correct.tudy:
Probably right -I recall reading similar about the new (it was
the early nineties)veg based engine oils-that was a DEFINATE no-no.
Thats probably why they never caught on.
I think things have moved on since then or the manufacturers would have lined themselves up for all sorts of warranty work without laying down the law first.
The owners manual on my C15 specified either type and made no point of cross contamination.
BTW-whats semi synthetic? -a mix of the two?
Ive just googled the issue and have skimmed though the rantings of countless internet experts
, but Martin-are we talking about preparing Sebastian Loeb's C4 or glooping up a 1.9D tractor