GL4 Trans oil QUESTIONS

Go to canadian tire and buy gear oil.  it doesn't really matter what kind.  There are no special requirements.  I use synthetic 75w-90 for better cold performance.  Or if you are a baller buy some redline mt90.

I've used Mobil 1 Devlac synthetic 75w-90 GL-4 in my P10 G20 and went to BG Syncro Shift II.  I found that the Syncro Shift II shifts nicer.  I also switched to Syncro Shift II in my Pulsar Transaxle and it seemed to get rid  of  a 5t gear clash on up-shift.  My price at the dealer, the BG was cheaper than the  Mobil.  Just an FYI on my experiences.

I run dump truck gear oil from a unknown container that was produced in the late 1960's :P works amazing but on cold days its not to fun to shift, but in the summer I have never wrecked a tranny or had any problems with it !

I just put in Castrol Syntec 75w-90. Got it at Parts Source.

Nissan specifies a GL-4 for the transaxle.

Not all GL-5 gear oils are backwards compatible.

Some contain sulphur additives that degrade the brass used in the syncros. 

Synthetic GL-5 may also be too slippery for the syncros to work properly. 

That being said, these are anecdotes and I'm sure many people use GL-5 gear oils in their transaxles and that works fine for them.

Personally, for 90s Nissan transaxles and transmisisons, all of which call for GL-4, I recommend Red Line. 

I use Red Line MT-90 (GL-4) for the transaxle and Red Line 75W-90 (GL-5) for the diffs and transfer. 

GL-4; Specified for hypoid gear service under severe service but without shock loading. This classification is essentially obsolete but is still specified by some manual transmission/transaxle manufacturers. Implies an EP/AW additive package that contains 30% to 50% less S-P additives than the GL-5 service classification. Some Marine Gear Lubes fall into this classification, especially the full Synthetic Marine Gear lubes and specialty blenders MT lubes that use high levels of esters.

GL-5; Specified for hypoid gear service but with shock loads and severe service operation. Usually meets Mil-L-2105D and in most cases, is the multipurpose automotive gear oil. Most 75W90 to 75W140 grades meet the GL-5 classification. This grade has a high level of Extreme-Pressure additives that could be mildly corrosive to nonferrous parts, such as brass, bronze and aluminum parts. Most of the modern GL-5 lubes contain metal deactivators that prevents attacks by the extreme-pressure additives. In addition to EP additives, these lubes contain rust inhibitors, defoamants, friction modifiers, thickeners, and Viscosity Index Improvers. 

LOL oil is oil

Thank you everyone,

NXPARTSSOURCE, I don't agree of what you've just said..  

I'm a baller, i used Redline MT-90

heheh just my two cents :D