The owners manual says that the diff should be filled about one inch below the fill hole. Is this correct? Can I remove the conventional oil and replace it with synthetic? What kind would you recommend? I thought the fluid level should be at the base of the fill hole? Thanks for your reply!

 

mine is a bout 1-1.5" below the hole, I needs that space for air I think, I also run Lucas and nothing else. I have ran it in diffs for years. the only problem is that it is expensive, so if you have to change your gear oil often due to water in it. It will cost more.

 

how do u know if u have water in your diff fluid

 

its kinda hard on an ATV because the diffs are so small so i just change mine often if I have been in the water which I always am. But in jeeps you can see it, the fluid starts to look milky, Its just a good Idea to change the fluid on a regular basis, and besides the gear is not that expensive, not even the synthetic