I've been pretty impressed with the results of changing the engine oil to synthetic during the first oil change that I'm considering doing the same for the rear end. Anyone have any experiences with using synthetic oil in the rear?

 

Never tried synthetic, I've had no complaints with PJUR Back Door though.

 

Until I clicked on the link I really thought it was a new car rear end lube.

 

BWHAHAHA! I thought the same thing when I saw the title of this thread...

 

Without a doubt.....POST OF THE DAY! Bwahahahahahahaha!!!!

 

I use Motul 75w90

 

another gay post?

 

I was going to go with the Motul but chose Amsoil synthetic lubes for both manual gearbox oil and rear differential with LSD. Motul just wanted way too much money for their lubes. I should receive them and have them changed out next week I'd think.

 

So....you'll be "receiving" something from Amsoil next week??

 

Synthetic lubes for gearbox and rear differential.

 

You guys crack me up! That'll teach me to never post on a Saturday night! Ok...several look like you've swapped to synthetic in the rear...but have you noticed any difference in performance, mileage, etc.? Was just curious.

 

Hey BB....think you could do a DIY on this??

 

I would use only the recommended fluids for a differential due to the LSD itself. Even if you went synthetic, it would have no impact on gas mileage.

 

The viscous limited slip differential is in a sealed box and never touches the rear end fluid. Having a viscous lsd makes no difference on the type (lsd or not) of rear fluid. You do not need to use the rear fluid which contains the additional additive to allow plate shifts if you have a viscous lsd.

In theory, the reduced friction in the rear end should reduce driveline energy loss, and improve fuel economy.

 

I'm glad you posed the question Silver37 because I have been wondering also. On my RX8, I switched out to Redline MT90 for the 6MT transmission and Redline 75W90 NS for the LSD and it really seemed to make shifting much smoother. I would be interested to hear what others have done or are thinking. Here is a link to Redline http://www.redlineoil.com/products_g...7&categoryID=7