What type and viscosity lube oil should I put in my differentials. I have a Corporate 14 bolt in the back with a detroit locker and a Dana 44 up front with a ARB air locker. I would like to change out the oil, but don't know what kind to put in. I would like to use a synthetic, but I don't know what range or brand.
Thanks for the help
Brent
1983 K5 350