I am finally buying my RX tonight and tomorrow I want to change the differential and transmission fluid to Redline synthetic. Which kinds should I get for each. I am kinda dumb when it comes to gear fluid and know nothing about what weight to use. Thanks

Adam Perrins

 

Use the Neo stuff that Mazdatrix sells. I've heard its even better than the redline stuff.

 

I had redline in my car and it felt the same as the stock stuff. I put the NEO in and it is awesome. The tranny feels like butter. It is a little more money buy well worth it in the long run.

 

in case you wanted an answer to your question instead of advice to buy neo...

diff takes 1.4 quarts of Redline 75W90 Gear Oil
tranny takes 2.5 quarts of Redline MTL

so 3 bottles of 75W90 and 5 bottles of MTL are almost a perfect double supply, to split cost with someone.

 

I put the 75-90 is both the diff and tranny...I disagree with someone that said it feels stock...it's better now... I would have liked to try Neo but I was pressed for time and couldn't find it.

 

I just changed from redline to Neo in both the trans and diff. Neo is better in my opinion.


I used there 75/90 HD Syn. gear oil for both - trans / diff.

I bought one gallon and one quart and had some left over.

 

well, with Redline, the 75W90 contains friction modifiers to aid limited slip, which is not something you want in your tranny. there you want higher friction to aid the synchros meshing, which the MTL provides.

so, of course you can get away with 75W90 Gear Oil in the tranny, but the MTL (75W80) is designed specifically for manual transmissions. if you insist on a thicker oil in your tranny, they do make "MT-90" a 75W90 version of MTL.

no idea if any of this applies to Neo, never used it.