what to use??????????
 

hey guys i bought a 64 gmc 3/4 with a 305 v6 real cool truck i got it for a old lady it was her husbands truck who died a few year before this the truck had been sitting for sometime i brought it home and got it running now i want to change some other fuilds like rear diff and trans its got a dana 60 rear what should i use for fuild? Do i need to add an additive? and also has a 4 speed trans what should i put in that? thanks guys

Re: what to use??????????
 

80-90wt hypoid gear oil, just fill to the bottom of the fill plug on the side. just make sure that it is not posi as then you will need an additive
ron

Re: what to use??????????
 

I just changed the fluid in my axle, the shop manual calls for a gl-4 hypoid gear oil. Most places sell gl-5 gear oil. I read on the "internet" that GL-5 uses more additives and could attack brass if there is any in the axle. Don't know if thats true so to be safe I just ordered what the shop manual called for. The only place I could find GL-4 was napa.http://www.napaonline.com/Catalog/Ca...229_0006410049 Or you could use synthetic gear oil, but I am not sure which one to get.

Re: what to use??????????
 

GL4 means the standard 80-90 wt gear oil some use the term multi purpose .
if you go into and auto parts store and ask for 80-90 wt hypoid gear oil that is what your going to get unless it is some kid who can only look at a computer

ron

Re: what to use??????????
 

The mobil website says gl-5 ok for axles but not certain transmission applications where gl-4 is specified so I probably didn't have worry about the axle. All they have in the parts store is gl-5 so I ordered gl-4 from napa.http://www.mobiloil.com/USA-English/..._Gear_Oil.aspx

Re: what to use??????????
 

Thanks guys for the input it does have a locer in it. im not sure its its like a clutch style or like a eaton locker or like a detroit locker. any ideas what they used?
:gmc2: