Editing Forums/Z31P/z31-repairs-forums driveline/Manual transmission gear oil

{{ForumImport
|op_user=mwolvinm
|op_date=2020-12-30 20:53:35
|post_count=9
|archive_url=/Z31performance_archive/forum/z31-repairs-forums/driveline/545703-manual-transmission-gear-oil.html
}}

'''mwolvinm:''' <small>(2020-12-30 20:53:35)</small>

What is everyone using for manusl

transmission gear oil these days? The manual calls for api gl-4, but all I can find is api gl-5. From what I’ve read gl-5 can be bad for the synchro’s.

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'''Espeed:''' <small>(2020-12-31 00:23:54)</small>

The last time I replaced the manual transmission fluid, I used Redline MT-90. I picked up a gallon jug off Amazon a few years ago.

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'''kaur:''' <small>(2020-12-31 11:51:49)</small>

GL-4 is highly recommended by a lot of people and I do join in. I shortly used some Motul oil labeled as GL-4/GL-5 once because I couldn't find GL-4 right away. It's not only potentially dangerous to the synchros, but it clearly shifted worse. After a cold start it was very hard to switch to 2nd without some grinding. I'm in Europe where Redline is hugely overpriced, but I found some Castrol GL-3/GL-4 oil that has worked just fine. But at least over here you really have to look well to find GL-4 oil.

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'''Gem84Znt:''' <small>(2020-12-31 13:10:09)</small>

I also bought REDLINE MT90 from Amazon. DO NOT let auto supply sales people convince you that GL-5 is OK to use. It will harm/destroy "yellow metals" as said by petrolium experts.

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'''mwolvinm:''' <small>(2020-12-31 23:27:23)</small>

That’s what I’ve read as well. So far, redline is cheaper direct from them than amazon. Just stopped at the local dealership for some rear cam seals and found out they sell gl-4 for $20/qt. That’s cheaper than redline here.

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'''kaur:''' <small>(2021-01-01 12:16:26)</small>

Nissan has quite a few gearboxes where they require GL-4 so they should stock it. Can't go wrong with OEM oil I would assume.

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'''badq45t:''' <small>(2021-01-04 02:39:18)</small>

I have used Redline with great results in the past for the Z, man I cannot remember the last time I swapped that oil out maybe due. I strickly use the Nissan OEM stuff for my 05' Xterra 6 speed as nothing else worked as well in it. My mechanic changed it out with whatever he had in stock in the X and it sucked, I made him swap to Nissan OEM synthetic and night and day better.

Redline works great, the OEM stuff is good too.

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'''88sinZ:''' <small>(2021-01-19 03:35:05)</small>

CNC Sta-lube gear oil 85w-90 P/N: SL24229 (32oz) alternate P/N: SL24239 (1gal) will be the most widely available, got it through NAPA but is avail. through amazon. The FS5R30A likes it.

Napa didn't carry it on the shelfs, had to ask for it by PN. Luckily their local warehouse is close by and they had it in stock.

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'''88sinZ:''' <small>(2021-01-24 03:27:28)</small>

glad to help mwolvinm! can't go wrong with dino-juice