Peter_02AMG

Hey Guys, I was thinking of getting my rear gear oil change out. Who has done it and what type of oil did you use?

thanks!

Peter

E55 PWR

Royal Purple Max gear is the best diff oil by far. Its 75w-90. It will give you increase in MPG as well as boost power a bit by reducing friction. While you are at it might as well do engine. It definitely made a significant difference in MPG and it was one of the biggest factors in getting me up to bout 23-27 city and 31-34mpg hwy (the other being crank pulley & intake & X-pipe). hope that helps.

Peter_02AMG

Wow!! your gas mileage is good!! i'm getting 13.7 mpg around town and I'm very easy on the gas padel.

Thank for the info on the gear oil. So 75W90 is good for E55.

thanks again!!

jimmydagreek

I agree with Omey, Royal Purple all the way! I changed my rear diff. and motor oil to RP. My gains in mpg weren't as significant but I'm in the mid 20's on the hwy.

E55 PWR

Ya, I had a lot of various mods though. K&N filters help, X-pipe helped a bit, Royal purple oils & crank pulley helped out by far the most. I was also at 3000ft altitude so thats slightly higher mpg than you would get at sea level, but theres no reason you can't get 30mpg on hwy in our cars, I didn't even get a chance to do headers, that would have helped out as well even more. 35mpg is probably about the absolute max you can possibly get but hey... not bad