Changing the rear axle seals on my 07 STR and wondered what brand and weight gear oil you guys like? I'm thinking Royal Purple. Also I know the book calls for 75w-140. But if I only drive the car in the spring, summer, & fall would a thicker weight be better? Like 85w-140? I realize that when car manufacturers put together vehicles and manuals, they need to be aware that people and climates will vary drastically. So they tend to state a "safe" for all climate weight.

 

We're not seeing them fail so just stick with OE spec.

 

+1.

Use whatever brand you like as long as it meets the OEM specs. There's little to be gained by second guessing the recommended viscosities.

 

Sounds good! Thanks guys

 

I used the castrol 75w140 gear which meets jag spec for the rear end.

The rear diff is an open diff unit and very simple internally. Any good clean oil close to 75w140 should do it.

 

I use the royal purple in mine, I prefer to have an oil that exceeds the standard spec plus on mine it quietened down the rear diff nicely and I know that the wear rate will be reduced. I would also say stick to the standard viscosity though.