Has anyone used Amsoil rear-end gear oil? A buddy is selling the crazy stuff and makesclaims that it is better than factory gear oil. He seems to think that it will boost milage. Anyone tryed it? Thanks Outboard

 

Amsoil makes very high quality lubricants. I doubt it will increase mileage, but it is a better product.

 

You would probably see little to no improvment on mileage unless you switched all your drivetrain to a synthetic oil. However, you would probably gain some longevity and run cooler temps on your drivetrain. Be carefull not to start using sythetic oils in an older engine as it has a tendency to leak around old seals. You can use it in a new engine and never have any problems with it for the life of the engine but old seals tend to shrink with it. Also, once you start using sythetics, you shouldn't switch back to a conventional oil.