Front diff fill-up

[kc2aku]

A fella on the diesel page quoted out of his service manual that the 9.25 front axle requires the Gm grape juice axle lube.  Does anyone else with the service manuals find this?  Here is the link to the post.

 

http://forum.62-65-dieselpage.com/ubb....=004131

[RyanbabZ71]

the 1500 4wd trucks take 80W-90 (non synthetic) in the front

 

THe purple stuff (gm fluid) is for the rear ends

[SoMnDMAX]

Any fluid meeting GL-5 spec is fine, whether it's 80w-90 Dino oil or GM's "Grape Juice" synthetic. The key is the "GL-5" specification.

 

I use the same lube in both the front and rear differentials.

 

Synthetic lube in the front will not hurt it at all.