Re: Multi-Vis Oils

["Wayne Graefen" <wgraefen@xxxx>]

Parts Doc Gary was seeking comment on why multi-viscosity oils are
not recommended. My $.02 is that was a consensus around the car
hobby for all the while multi-vis existed .... until about 10 years
ago. I read an outstanding article in the Classic Car Club of
America publication to its members by a very highly placed oil
industry engineer regarding the fact that it was time to end all
that controversy.
While it had been true that some of the chemical blends required to
make the oils change viscosity depending on temperatures were often
less than ideal, particularly on very wide viscosity number spreads,
that the time had come to accept them and in fact embrace them
because for the old cars in particular, using multi-vis was going to
give the best protection at start up during our occasional use of
our cars and that the chemical package of today's multi-vis oils was
so superior to single-vis oils that they simply were a necessity for
old cars.
Now I would remind you that some of his readers had million dollar
Duesenbergs in their collections and other great classics so this
man was putting his carreer and reputation on the line and you can
bet would have been sued by a Hispano-Suiza owner if proven wrong.
So for our post-war near equivalents to the great pre-war Duesies, I
took his advice and offer it for your consideration.

Wayne