Gear Oil?

[splitfinger09]

I believe the reccomended weight is 75W-90 for the differential. I have 75W-140 Max-Gear oil by Royal Purple. Would it be ok to use that weight? Also is the use of synthetics ok to use in my diff?

[Jays00ss]

yes, its ok to use that weight and synthetic oil is fine. However if you live in a cold climate, you might want to warm up your gears a little without haulin ass at first. + your gas milage will suffer with the heaver oil.
Synthetic oil lets you run a lighter weight and gives you better protection like a heavier oil.
I run royal purple 75w90 in mine. No problems what so ever. If you have a lot of miles make sure you check your pinion seal as they tend to leak. good thing to check your level at least every 6 months to yearly.