I am having shifting issues and am told that changing my fluid may help. Is it necessary to replace the Diff fluid (75w90) as well as the Manual Tranny fluid (mt-90)... Or just the Trannt Fluid?

Was lookin around for this question but didnt find it in particular.

 

Change both at the same time for peace of mind. MT-90 in the MT and 75w90 in the diff'l. I like Redline fluids, as many here. Race Roots here stocks it as does Summit Racing and a number of others. You'll have to buy 2 qts of/for each. It helps to have a quart hand pump too; available at Pep Boys (same one as used for nautical outboard motors).

DIY:

https://www.rx8club.com/showthread.php?t=35115.html

This link has nice orientation pictures:

http://www.5cats.org/rx8/trans_diff_refill/

 

Thanks Very Helpful. But the Hard shifting / catching when shifting would be mostly tranny i would think..

 

yes that most likely will be fixed if u change the tranny fluid .

 

Thanks