The manual states a hypoid gear oil, which is an EP gear lube, extreme pressure, or High Pressure. Valvoline makes a few different gear lubes, make sure its EP (Hypoid Rated) Hypoid is the way the gears are cut. 'Almost' all final drive lubes have LS additives (friction modifiers). I know personally of someone who used gear lube in the front diff without friction modifiers (It wasn't Limited Slip rated), and he had to add it after, because making turns was like having a front locker locked lol..I have Valvoline gear oil 75W90 with the friction modifier that is used for my truck. Do you think I could use this in my 03 Rincon?