Thread: Gear oil GL-5

It's time to change the oil in the trans. I'm not looking to put Redline or anything like that. Found this stuff at my local O'Relly's Master Pro Chemicals 80037 - Gear Oil | O'Reilly Auto Parts if I could find a conventional GL-4 i'd get it. But I can't find GL-4 anywhere in SD. It does say "Suitable for use where the following API service designations apply: GL-2, GL-3, GL-4, and GL-5". So guys, is this stuff safe to put into my trans?

If it is for GL-5, no.

What is wrong with Red Line?

I'm not sure if I should get it. Description says it's safe to use in a GL-4 trans.

I'm not paying $12-$13 a bottle for gear oil. I don't even race, or drive my car hard.

I don't race or have a powerful car yet I use it. I dunno, its your parts and money, put it in there and see if your brass synchro's get eaten up or not. You will know if your transmission no longer shifts anymore.

Our transmissions are GL-4 spec.

GL-5 transmissions do not have brass in them. This product could damage it or not. Red Line is good shit and you will never have to change it or mess with again. But you live in SoCal so what do I know

Look for Penzoil Synchromesh, not that expensive and im sure a local store should carry it.

That's a lot of money though. $13.50 a quart, I need 4 quarts right? Sucks there isn't a GL-4 conventional oil out there.

Thanks NissanGuy. I'll look into that.

You will need 4 quarts, yes. Not all of them, but over 3 quarts indeed. There are alternatives, you just have to find them. I think I found Pennzoil Synchromesh for 8 bucks a quart at wally world.

Just avoid anything GL-5 for the sake of your brass synchros. Good luck.

Thanks Viprdude. I've read that GL-5 gear oil is a no no in Nissan transmissions. When I had my Z32, I ran nothing but Redline MT-90. When I saw that oil at O'Reilly's I thought it would be safe to use, as it did say ok to use in a GL-4 trans. That Synchromesh stuff will be good enough for me.