>
> there's been a slew of traffic about this on the porsche list; this is
> a sampling. One of the claims was that Castrol GTX caused his cam to
> pit, and that it stopped when he switched to Valvoline Turbo...
>
> ------- Forwarded Message
> (message about relative merits of different brands of motor oil deleted)
5 or 6 years ago I had spoken to several people who had problems with their
engines that they swore were caused by Castrol oil. Supposedly Castrol
would sludge badly. At one point back then, I put castrol in at an oil
change, and it was strange. When pouring the oil in, it had little waxy
granules suspended in it (this is the brand new oil being poured in). Sure
enough the car showed symptoms of oil that was massively the wrong weight,
and I changed the oil again to a different brand, and the problem cleared
right up.
For the next few years, I swore never to use Castrol, but one time I
happened to use it for an oil change (I forget the circumstances), and
it didn't have the little granules, and there was no problem with it.
problems.
I've recently heard people say that Quaker state has excessive wax, and
will build up little structures in your engine. I've also heard people
say that Kendell is terrible (no reason, but I've heard several people
say this), that Valvoline is either good or bad depending on who you talk
to, etc. The only oil that I've heard consistantly good things about is
Mobil 1 (I would buy it if only I could figure out what grade to get!!).
A few years ago Consumer reports tested motor oils, and their basic
conclusion was that the stuff changed on a batch by batch basis, and
that the brand had very little to do with what was in there. To support
this, I have seen Castrol 20W50 anywhere from a very dark green to a
honey colour. If I remember they found several brands that didn't meet
the specs they claimed to, but all but one brand did meet them on a
second bottle purchased at a different time.
It seems to me that a lot of this oil preference stuff is probably based
on the one time that someone got a bad batch of the particular brand, after
which they swear that that brand is evil.
Joe
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