askoop wrote:
anyone run 75/90 in front D30 diff? any ill effects of doing so?
Up until I took the front diff out of my 03 it held Amsoil Severe Gear lube in the 75W90 weight and no problems with quite a bit of light gas pedal moderate wheeling.
The specs I see vary from 75W140 to 75W90 depending on year. Unless you are wheeling real hard and are heavy on the gas pedal I don't think it will be much of an issue if you are running a good quality synthetic gear lube.
FWIW, My wifes 04 has the new Severe Gear 75W110 in it and has been on numerous wheeling trips including this past year to Moab again.
Note: I did blow up a front diff in my 03 once. It did have 75W140 in it but I do not blame the gear oil for the failure. I think I just got a bad diff that I finally found the weak spot on after Many wheeling trips. It was NOT Amsoil Severe Gear then FWIW. Not to say it couldn't have happened if it had been.