I'm looking to change my manual transmission fluid. I looked at the manual and it recommends GL4. I went to the local dealer and asked for three quarts (wasn't sure how much I needed - neither did they). The parts guy brings me three quarts of Pennzoil GL5 80W90 gear oil. I ask if they have GL4, and he goes to the back to ask the parts manager. The parts manager told me that GL5 is what they've been using since the 4th gen Maxima came out, and they haven't had any problems with it.

Unsure about what to do, I ask him if I could bring it back in the event that the shop who flushes the fluid for me tells me to get GL4. Basically, I wanted to know if I could return it if Maxima.org recommends GL4 and tells me not to use GL5. The guy gets angry and says "why would they say that? Fine, bring it back but I'm going to charge you a handling fee." He tells me that GL5 is the same as GL4 except it has oil for LSD.

So now I'm not sure what to do. Doing a search on the test site, everyone seems to recommend GL4, and in particular synthetic oil. I'd rather stick to regular oil because I've also read about leaks that some people experience, coincidentally after switching to synthetic.

Should I return the GL5 gear oil they gave me, and buy GL4 gear oil elsewhere? Where can I find GL4 gear oil, what viscosity should I get, and what brands do you recommend?

Thanks!
-Brian.

 

I've been through this one when I changed my clutch. Just play it safe. Give back the GL-5 and get yourself some GL-4. I personnally use Redline MT-90 GL4. Its good stuff and consistent with what the manufacturer recommends.

 

Do NOT use a conventional GL5 gear oil in the Maxima's transmission. The EP additives in it will attack the softer metals in there and cause a very notchy shift feel and degrade synchronizer life considerably.

 

Anyone know where I can find GL4 gear oil? All the local places don't seem to have it or know what I'm talking about.

 

why not some redline mt-90?

 

Do yourself a favor and upgrade to the full synthetic. The synthetic gear oil will last twice as long.

Your best choices are the Amsoil Series 2000 75w-90 or the Redline MT-90. Both are top of the line products.