gear oil for 5MT?

[Fugazi]

I hate to clog up the forum with stupid newby questions like this, but I'm not as good with cars as I am with computers

A tranny oil change is in order and I'm wondering if I can use some 80w90 GL5 gear oil I have sitting around. I was told by a friend that it should work, but I'm a little worried because its limited slip. Should I go out and get something else? If so, what kind?



"Carquest premium 80W 90 Gear Oil"
"limited slip for top-off only, API service GL-5. GL-4, GL-3"

[entirelyturbo]

You have no limited slip. Your transmission has an open front diff, a viscous and sealed center diff, and an open rear diff.

Yes you can use plain old GL5 80W90, in fact I recommend it. Read my stickied thread about grinding synchros and you'll understand why.

[Fugazi]

So can I use this stuff I have right now, even though it says its for limited slip? Thats what I'm concerned about, I have no idea if it could cause problems.

[Bubba-Ugly]

I would use a 90W-140 gear oil in the differentials and transmission. You may need the protection from heat because of the desert and mountain roads in your area. (Bend, OR) I once tried AMSOIL synthetic gear oil in my transmission and differential, but it would not cling to the synchros in the gear box, and cause terrific gear clash. I had to go back to a regular gear oil to get the transmission to quiet down.

[Legacy777]

That's way too thick oil to run in these trannies.

75w90 is what the manufacturer calls for, however 80w90 will be fine.

[greg donovan]

mine has GM syncromesh in it. i believe it is 75/90. not sure as the previous owner put it in. i think it feels very good. felt nice in the cold weather today.

[BAC5.2]

Redline 75W90NS. AMAZING stuff.