Transmission oil question..., which one would you recommend? Options

[malpaso]

I need to change tranny oil and I have had just one recommendation so far:

SHELL SPIRAX GSX 75W/80 (80W) GL-4

What do you think about that? What tranny oil you have been using? And also anyone here know what that "GL-4" grade means? (I have seen oils with GL-3 or GL-5 grade). Thanks for opinion...

oh.. and I forgot: how much I will need? 2litres?

This post has been edited by malpaso: Apr 19, 2007 - 3:01 AM

[mikew04]

http://www.pennzoil.com/products/gear_oil/syncro_fluid.html

80 is the viscosity, or how resistant to flow the oil is. like the 10 weight in your motor oil is more runny than an 80 weight in your tranny. the w stands for winter which means you can use it year round. the gl3 and gl5 i believe are service ratings for heavier equipment, so you shouldn't have to worry about that

I dont think they offer syncromesh in other viscosities, although I could be wrong.

[alltracman78]

No, for your trans you want ATF Dextron III.

http://www.pennzoil.com/products/gear_oil/syncro_fluid.html

80 is the viscosity, or how resistant to flow the oil is. like the 10 weight in your motor oil is more runny than an 80 weight in your tranny. the w stands for winter which means you can use it year round. the gl3 and gl5 i believe are service ratings for heavier equipment, so you shouldn't have to worry about that

I dont think they offer syncromesh in other viscosities, although I could be wrong.

Close.
80W-90 GL5
80 is how viscous it will be at 0*F. In this case, it will be as viscous as a 80 wt oil at 0*F.
W stands for winter grade, and goes with the 80 to signify it's viscosity is measured at 0*F.
90 is how viscous the oil will be at 212*F, it will be the same as 90 wt oil at 212*F.

GL5 is basically the shear strength of the oil [how well it resists being broken down under pressure].
As far as I know, only GL4 and 5 are used right now as a spec for gear oil.
GL5 is a little tougher, but is also more corrosive to yellow metals, such as bronze and copper.
Your synchros are made up of alloys of these.