I'm going to change Xmission and Diff oil this weekend, and I'm changing from Redline to NEO 75-90. Not having any Xmission problems, just a notchy shift into 2nd and 5th.

After a week or so with the NEO I'll post my thoughts comapring the Redline and the NEO.

 

Please do. I was wondering how NEO was. I'm actually changing my Amsoil and trying the switch to Redline MT-90 this weekend. How did you rate the Redline?

 

I've used Redline MTL in the xmission and Redline 70-90 in the diff for quite a while. No problems at all from the diff. Like I mentioned before, shifting into 2nd and 5th while under load can be an adventure. I have a Mazdatrix short shifter installed.

 

Gosh, I missed that you said notchy in the first post. I did notice it seems watery when I poured it in when compared to the Amsoil. Not sure I like that much.

 

I made the exact change as the OP a couple years ago to NEO HD 75-90. Nothing dramatic, but I think there was some perceptable improvement. The Redline that was in there was about 4 yrs old.
FWIW, where I saw the most improvement on smoothness was when I re-greased the shifter ball and lower bushing. The FD FSM specifies it and I think it's overlooked some.

 

My initial thoughts:
1) Shifting into 2nd and 5th goes much smoother with the NEO
2) Shifting into reverse could sometimes be a chore. Now the shifts into reverse go smoothly.

The Redline that came out had about 10K on it and was a bit discolored, but not much. I don't think it was worn so much that it couldn't do its job. Its synthetic after all and designed for extended wear periods.

Its been a while since I changed out the shifter boots, bushings and leaf springs. That should make shifting even better with the new gear oil in the Xmission.

More to come after I've put some more miles in various driving conditions on the NEO.

 

All shifts with NEO seem to be much smoother than with the Redline. Under load from 1 to 2 and from 4 to 5 much smoother, no grinding. Downshifts from 5 to 4 very smooth. I would completely recommend NEO after what I've seen. However: NEO is expensive. Is it worth the difference from Redline?? For me, yes. The problems I had seen prior to changing to NEO all went away.