What's everyone's opinion on diff fluids? And weights? My dad was a mechanic and suggested Lucas or royal purple. He also said it wouldn't hurt to go a weight up with oil to just help the gears out and run smoother. I know 75w90 is what gos in my d44. So he suggested 75w140. Any thoughts?
If you are towing, then use the 75w-140. If you are not towing, then either viscosity will work.
As for Brand, Conventional verses Synthetic, they are all good. (No oil wars please). The main benefit is that you change it!:yup:
I don't tow so I run Lucas 75w-90 Synthetic. That is what was available at my local parts store. It's probably no better, or worse than any other gear lub!
