RedLine vs. Royal Purple

[KenC]

I need to replace my Transmission and Differential fluids and I was wondering whether I should use Redline or Royal Purple. Has any one used both and have an opinion on either of them?

[Spaz]

Redline is the shit i've used it in both of my e30's and it works wonders....gets rid of that hard shift when cold....i'd stick with the tested and commonly used brand which is redline...

mtl: for the trans
75w90: for the rear end


-cam

[BeirBrennerE30]

i cant say anything about royal purple since ive never used it myself but what i can say is that im a big supporter of redline fluids no matter what kind... ive never had any troubles and shifts are really smooth... one of my friends changed from some otehr junk to redline in his tranny and actually saw about an extra couple horse at the wheels... no one could believe

[kidrobot]

Royal Purple isn't very good I used it twice and switched to Readline!

[JRowe]

Everything I've heard about Royal Purple is that it has great initial results, but breaks down much more quickly than other synthetics. Go with redline. It's proven itself to many bimmerphiles.