Date: Thu, 13 Feb 2003 14:16:14 -0700 From: Inky <newsgroupinkynopsamail.com> Subject: Re: use fossil or synthetic oil?
In that case, I will definitely stick w/ the non-synth. My car already has a slight leak. Sounds like the synthetic will just magnify the problem. Thanks for the tip. -- Christian '85 900 8V (160K miles) On Thu, 13 Feb 2003 13:50:09 +0000, Grunff <grunffnopsam.com> wrote: >Paul Halliday wrote: > > > On older cars where the oil >> used by previous owners is not known, there is a risk that synthetic oil >> will clean away mineral deposits and slight leaks may occur, but I've been >> lucky. > >"Slight risk"? "Slight leaks"?? Paul, I suggest you've been >*very* lucky. > >While I'm in no way disputing the fact that synth is very good, >and especially appropriate to turbos, there is a real, big >danger of *major* oil leaks when switching from mineral to synth >at higher mileages. > >I've personally experienced this twice, and seen it happen to >others many times. I think the main mechanism is seal shrinkage >(mineral oil swells seals quite a lot, which compensates for >seal wear, whereas synth doesn't). > >Unless you're happy to change your front and rear crank seals, >and probably your oil pump o ring, then don't change from >mineral to synth at high mileage. > >This doesn't apply to the OP - carry on using synth.