Any reason MT90 wouldn't be compatible with factory fill conventional gear oil?
 

I've decided not to replace the gear oil in my 97. I was going to top it up, if it's low, with MT90. Are there any forseeable problems? :) Thx!

i wouldn't recommend mixing a synthetic gear oil with a stock one based off conventional oil

Um why even use Redline if you are just going to cheap out and top it off? Do your tranny a favor, drain and refill it. It's probably been 30-50k since it's seen new fluid.

You've probably noticed that it's almost impossible to get a GL4 fluid. I've come to realize that Nissan doesn't have a recommended change interval on their gear oil. Ie. it's good for life. So, for my 97, to save the $35 to buy four more quarts of MT 90 (I already have a half quart remaining from my 00 change last year), I wanted to merely make sure the fluid level is good, and leave it at that.

no fluids are good for life. Its not a physical or chemical possibility

Hey I'm just rehashing what the manual and guys at Nissan stealerships said ;) It seems a stretch to me as well, I agree, but I'd think that if they thought it should be done they'd say so, to get some cash!

i don't know why you think you can trust nissan dealers. Here is some info for you taken from www.nissanusa.com:

auto or manual fluid change every 30k miles or 24 months aka "Replace differential oil (limited-slip, conventional)"
http://www.nissanusa.com/form/0,,act...-51041,00.html

and btw, it is listed in your owners manual. It even tells you how to drain the fluid.

I'm pretty sure my 97 has only an inspection schedule - not a replacement one. It has schedule 1 and 2, which, according to that site, does not call for an oil replacement (I only checked 30k,60k,90k though under "manual transmission oil"). However, you're right that the premium schedule does call for it. This is the kind of definite information I needed. Thanks for the link - I'm off to my local redline dealer to buy another 4 quarts afterall :)

definitely vital for us to follow the premium schedule. We aren't grandma's driving around in maximas. :goofy: