94 Nissan P/U Manual Trans Fluid

[bigbillm66]

Anybody know the type of Manual Tranny fluid to use in a 94 Nissan P/U. Repair manual says API GL-4 (Gear Oil). Autozone only had API GL-5. Not sure if I can subsitute GL-5 in place of GL-4. Any Thoughts?

Bill

[bigbillm66]

Did a google search on "Nissan API GL-4" and found the following. Looks like I will have to find some API GL-4.

API GL-4 and API GL-5 products typically use the same extreme pressure (EP) additive system, with the API GL-5 having about twice the concentration of a API GL-4. In service, these additives become active under extreme load and temperature when the protective oil film can be squeezed away. EP additives work by forming wear-resistant compounds with the metal of the gear tooth surface. As the gears mesh, these compounds shield the gear teeth from direct metal-to-metal contact that would cause wear and damage to the gears. If too little of the active additive is present, proper protection would be compromised. Too much of this additive could cause excessive chemical corrosion of the gear surface. If an API GL-5 gear oil is used in a application where API GL-4 gear oil is called for, chemical corrosion of "yellow metal" components may occur, such as bronze synchronizers, brass bushings, etc. This may lead to shifting difficulties or shortened equipment life.

Good instructions too @ http://www.jimbennett.net/replacing_...mission_fl.htm