Gear oil question
 

I'll be changing my gear oil soon. If I use Redline or Royal purple, do I have to also add the limited-slip additive? I think these gear oils already have it in them...but I just want to make sure.

Thanks

Not sure of Royal Purple but Redline has it already mixed in, unless it has the NS suffix.

I fyou use the correct RP, you are good to go.