<VV> Conventional, Synthetic Blend, Full Synthetic

[R. Byers]

Eric S. Eberhard writes " In theory you can extend your oil changes, I do not
as the dollar difference is not large on a Corvair!  Instead, I am sure I
am extending my engine life."

The issue is greater than just being cautious.  At very least, it is the use
and disposal of used oil for which we should be concerned.  The address below
seems to address this issue rather succinctly.
.http://www.bestsyntheticoil.com/amsoil/bigoil.shtml

Be this as it may, I have myself seen leaks appear through using synthetic
oil.  In the particular case of a Jeep engine, the sludge was rather severe
inside the valve cover which I pewrsonally removed after the owner complained
to me, the dealer.  Although synthetic oil will go a long way into renewing
hardened gaskets, in this particular case, apparently the grunge was being
washed away by the synthetic oil and thus began the leak.  Fortunately the
owner was somewhat apologetic when he saw the sludge.  We cleaned the inside
of the valve cover and replaced the gasket and the leak, of course ceased.
What worried the owner and me, of course, was whether the sludge build-up
would one day block one of the oil passages.  Two years later he was still
driving it with no leaks and no engine failures.
Ron Byers
Largo, FL