[BigwheelGoat]

I have 300 miles on it and the rear seal at the hub and final gear has leaked all the gear oil out and the only decent stuff I can find is slick 50 which is 80-90 not straight 90w :/

 

[rynosback]

Amsoil also makes a synthetic 80w-90 gear oil. I put Mobil 1 75w-90 in mine.

 

[Wanted]

 I put Mobil 1 75w-90 in mine.

Ditto. Good luck finding straight 90 weight gear oil. I've never seen it. I don't know if anyone even makes it.