[TR] Controversial subject...

[Jeff Scarbrough]

At the risk of opening up a can of worms, or beating a dead horse...

In my new overdrive transmission, I plan to run Brad Penn GL-4 80W90

http://www.penngrade1.com/Products/Gear-Lubricants/GL4-SAE-80W90.aspx

as directed by British Leyland since the car was new.  The rebuilder
of my overdrive unit says I should use 30-weight non-detergent oil.

I understand that the weight of motor oil is measured differently than
the weight of gear oil, and that there isn't a whole lot of difference
in the viscosity of these oils.  Looking at the specs, I see that the
80W90 has a viscosity of 15 cSt at 100C, while the 30 weight break-in
oil is 11.3, and the 20W50 motor oil is 20.0.

I read all sorts of stories about pressures locking parts together,
etc., and I wonder if I am over-thinking this...

Jeff Scarbrough
Corrosion Acres, Ga.