75w90 MTF and 75w90 diff oil- same thing?

[trintrin]

I am changing the transmission fluid in my 2000 5 speed Prizm. I am in a time crunch (the old fluid drained out a ripped axle seal), so whatever the local place has will have to do. The manual says it takes 75w90 weight oil- does it have to be designated as manual transmission fluid, or will any thing of the right weight work?

Also, this car probably ran with only about of pint of fluid in the transmission for probably a few hundred miles before I noticed the leak. It still seems to work fine, should I worry about long term effects?

Thx...

 

[mechtech2]

Rear end differential oil is good for bearings and gears in any situation.
It may be friction modified for limited slip applications, which is the wrong way for good shifting in a manual trans. Also it may be more corrosive to yellow metals [synchros].
Dedicated manual trans gearbox lubes are the only thing I would use in a stick shift. It will shift much better .
Redline MT90 or Amsoil's latest offerings in that weight would be my choices.
All you can do it drive it. Worrying about it won't help. But keep your eyes and ears attuned to how it sounds, any leaks, and it's performance/shifting.

 

[o2man98]

It would be best to replace it with a GL-4 75w-90. GM calls for part number 12346190 or equivalent.

The Amsoil example would be http://www.amsoil.com/storefront/mtg.aspx?zo=1132530

Ken

 

[sprintman]

Amsoil or Redline would be my choices. I have RL 75W90NS in Outback trans, Redline MTL in BMW 5-speEd. It was locally available ulike Amsoil dealers all interstate hence my choice.