EP and Non EP Oils

[jandarah]

About ready to do some oil changes in engine, gearbox and diff. Looking at one shop manual, (Brooklands),it specifies SAE90 Non EP oil in the gearbox and diff. The Haynes old shop manual is different. Are EP oils ok in the gearbox and diff? They seem to recommended for every model.

[76was124]

You can search the forum for lengthy discussions, but since the transmission gearbox has brass syncros I use non EP lube which factory spec calls out as a GL-1. Which is still available at some NAPA stores and some farm/tractor supply stores.

Unlike the transmission, there is no brass in the rear differential so EP is ok for the rear end ( not for the trans).....Factory spec is 80W/90 EP for the rear end, and I think the steering box too.

[jandarah]

That explains a lot, thank you very much. I will check it all out tomorrow.

Cheers

[divace73]

ignore what haynes says and throw that book out....there are some incorrect torque setting in one of the haynes manual that will cause a cam wheel to fall off!!!

EP oils usually contain sulfur as the EP ingredient which will eat away the brass synchros, so generally avoid them (some redline products are okay as they do not use sulfar)

[jandarah]

Cheers, thanks David, I am becoming more knowledgeable on the subject every minute.