DeTomaso Mailing List: May 2000, Message #144

I have never used Synthetic oil in my ZF but I can tell you one thing.  I
dont like Valvoline 80W-90.  I used it two years after using cheap farm
supply store oil for 11 years.  The valvoline seemed too thin to me.  The
ZF had more gear noise and shifted poorer in those two years then ever
before.  I had actually thought about buying a spare ZF.  It also leaked
bad.  Before the road to Vegas I bought some of that cheap farm store OIL
and changed the ZF life blood.  On the way out the ZF was quiet and shifted
better than ever.  The stuff I used is Traveller 85W90 and is GL-5
approved.  I had the ring gear safety wired two years ago and Cory Gehling
said the trannie was in great shape.  I have also had no change in shift
quality (except for the valvoline) in the last 40,000 miles.

So there goes to say, higher price does not always mean better

Dave "cheap is good??" D

PS, the biggest engine failure I ever had was using Valvoline oil.  From
then on I use Penzoil.