Synthetic oil in an older vehicle

["Ed Mathews" <Ed@xxxxxxxxxxxxxxxxxx>]

Hey,
     I'm the new (and enthusiastic) '95 325i owner.  The car has 130K on
it.  I've always sworn by Mobil 1 for all of my cars, in that after a
few changes with it, it seems to make a noticeable difference in how
clean the engine stays.  And I've noticed that after the 3'rd or 4'th
change the Mobil 1 oil also seems to stay much cleaner on the dipstick.
I've used it in my VW, Porsche, Honda, and Chevy with similar results.
I've also always used it only after the engines had used conventional
oil for the first 50-75K.
     I've heard the warnings of oil seal and gasket problems in cars
that have never used it through the Porsche list, but I've never
experienced that, or actually ever heard of anyone who "first hand"
experienced it, so I've dismissed it as folklore.  Now, the BMW mechanic
(comes highly recommended - seems knowledgeable and friendly) that is
inspecting my car tells me not to use it because he's had it cause
problems with seals with cars that have never had it before.
     So now I don't know whether to believe this or not.  He says
Castrol is better than other conventional oils, and will clean and
protect the engine as well as Mobil 1.  I've always considered most
dinosaur oils to be pretty similar if they meet the same API rating, and
it sounds to me like he's got a deal with Castrol.  But he is definitely
more experienced than me with the guts of BMWs and even all cars for
that matter.  Any thoughts?  Anybody ever really seen this mysterious
synthetic oil seal problem first hand?  I'd really like to have a
mechanic I can totally trust here, so I'm kind of hoping someone tells
me they've seen the problem.

Thanks,
Ed
http://lightandsilver.com 

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