G80 Gov locker info

[millsroger]

I posted in suspension re "bunny hop", in searching for cause, I think I found it, Eaton kind of calls this "slip stick".

Quick recap of what I found, 1989 is a break year, before that they use Mineral oil with a LS additive, from then on they used synthetic. It is NOT reccommended to use synthetic in the earlier units due to swelling of seals.

I attached a word doc with what I found FYI.View attachment GM Eaton G80.doc

 

[millsroger]

Sorry----transposed year---should be 1998.

 

[Jorge6.5]

So no synthetic fluid in the pre '98 trucks? Not even amsoil?

 

[millsroger]

Jorge, That's what they said. Apparrently Eaton changed the clutches and Dana changed the seals. Mine acted like it had synthetic in it, at least according to their statements. I do know that after I pulled the cover, cleaned it out and put straight mineral oil in it that it now acts right. I just hope the seals are ok.

 

[Jorge6.5]

What fluid did you use? did you use additive of any kind? Thank you

 

[millsroger]

Four pints Penzoil, 80-140 API GL-5 plus 4 oz LS additive then premixed and filled on level ground. I found a one gallon pesticide pressure jug at a yard sale for 50 cents and used that to fill with, just cut the nozzle off the end of the wand--I warmed it up some, but it works great on ATF or engine oil--no dribble or spill. Washed out first, duh.