X-Source: The Hotrod Mailing list
Date: Jan 1994
From: Carl Ijames <ijames@helix.nih.gov>
Subject: Re: Oil
X-Sequence: 7390

>I was dumbfounded and asked him how he could tell.  He
>pointed to a greenish deposit on the inside back of the block
>and said that Pennzoil always left that kind of a deposit there.
[snip]
>My current choice is Castrol.  I don't like their advertising
>but their oil seems to be OK for my engines and driving
>conditions.
>
>Bob Hale          hale@brooktree.com

My experience is a little dated, but what the heck :).  In the mid-70's I
tore down an Olds 455 with 90,000 miles which had received Quaker State and
a filter every 3,000 to 4,000 miles since new.  Under the intake manifold
the sludge was so thick that I had to dig down 1/4" to uncover some of the
pushrods.  Sludge was up to 3/4" thick in places.  I asked several mechanic
friends and they all said that that was normal for Quaker State.

After this I rebuilt our '68 VW (air cooled 4 cylinder) and started racing
it, along with a lot of street miles.  It too had had Quaker State in it
and had a good coating of sludge.  I switched to Valvoline Racing Oil,
since that was what all the local racers used (in their water cooled V8's).
 I popped the valve covers off about every 1,000 to 2,000 miles to check
the valve lash, and always noticed some sludge buildup starting in the
corners.  The oil was changed every 3,000 miles.  I then switched over to
Castrol GTX and everything stayed spotlessly clean ever since.

My conclusion was that Quaker State was junk, Valvoline was ok in an engine
that didn't see extreme heat, and Castrol GTX was the best.  I think all
these oils were rated SD, the highest rating at the time.  I run Castrol
GTX now in my turbo Regal.

My $0.02 worth,

Carl Ijames     ijames@helix.nih.gov