oldtexasdog

I am doing a rear gear change this weekend on a 08 GT to FRPP 4:11s. Which is better synthetic or reg gear oil and why? Also what would be a good modifier to use?
Thanks all for your time and input.

riskyfool

I'm in the middle of doing mine right now too. I bought Royal Purple. It says it doesn't need modifier but I've read a lot of people still put it in anyway. I'm going to try it without first, and I hope it's a good oil because this stuff is expensive!

mwinter501

Synthetic will always have better breakdown properties (IE less due to heat and whatnot). I figure: you will only be going in there once or twice, might as well put the better stuff in now.

As far as modifiers go, I can't help you.