Fluid Questions

I'll second this based on my own experience....I tried a synthetic GL4 in my T90, it was NOT happy! Simply didn't shift well. Went back to regular GL4 80W90 & all is well.

 

They said here that Sta-Lub GL4 is what we should use in our Transmission, Transfer Case because of the brass in the transmission, so I used it in my axels too. Old School Jeep, Old School Oil, is what I got out of it. Sta-Lub is available at Napa.

 

Does the overdrive have oil of its own or does it share transfercase oil?

 

the overdrive is lubed from the transfer case and to some extend shares oil from transmission. So I use stalube GL-4 in trans and transfer case.Differentials get GL-5 with a bottle of friction modifier in each for Powr-lok's. mike

 

Any reason gl5 80/w90 wont work its cheap at wallyowrld and im going to change it very soon again since theres water i wats in there but no real rust

 

GL5 isn't compatible with the brass synchronizer rings on older transmissions.

 

Cool thanks i figured there was a reason. Still learning bout these.

 

The GL5 in a jug from Walmart says "GL-5, GL-4 compatible" or something to that effect. To me this means it won't harm the transmission, but no guarantee. That's what I have in the axles of my old Jeeps. The CJ-6 has the StaLube GL-4 oil in the trans/TC. The J20 T-18 currently has the Walmart GL-5 and it seems ok, but I expect I will change it next time it's in the garage.