I stand corrected then, it was a guy at a local parts store that recommended 80-90.... Looks like I have some fluid to change again, and an autozone employee to tear into.

Just looked it up in the service manual, you are correct. 80-90 is for the rear, 75-140 is for the front. My mistake.

 

I've had my truck for the last 15-16000 miles, and have never checked the diff fluid levels, but there's a whine from the front while in 4WD. Now that the subject's been brought up, and I know the correct fluids...is there a gasket between the diff and the diff cover, or use RTV, or could it possibly be as easy as pop the bolts out, clean diff out, clean the mating surfaces and rebolt it up, then refill to just below the fill hole??

 

Just use rtv. Personally I use the ultra black, it says max oil resistance. Yep that's all it is to it. Just fill till it's right below the hole and that's it.

 

Cool, thanks for the correct fluid levels and advice : )

 

No problem

 

The only thing AutoZone counter clowns really know is "Would you like some fuel injector cleaner today? We're having a special on Lucas". Consult the manual or ask here, but never trust a counter clown!

 

ha ha ha that is exactly what they say everytime... well i do have a buddy who works there and his manager gets mad cause he doesn't tell me

 

any GL5 gear lube is ok for the axles. 90, 80-90, 85-80, 75-140. it doesn't matter. its just heavy gear lube. but if you have a limited slip (unlikely in front, possible in rear - add the friction modifier.

i use black RTV for everything. i don't like orange or blue colors shining at the seams. just clean both surfaces, run a thin bead all the way around including around the bolt holts. let it sit for a few minutes to semi-cure. install and torque to spec. let cure for a couple of hours.

as said a small amount of gear lube will come out of the cad when you remove it. 1 or 2 cups. the factory gasket is a fancy cork/aluminum thing. mine was a little confusing because i could see the cork and kept scraping at it, and didn't see the thin aluminum backing plate that needed to be pried loose.

 

This is the best in my opinion .

 

lol counter clowns, i have a napa, autozone, and advanced all near my house, and ive seen the same high school kid work at all three.
every time i see him in the store i will only buy a pine tree air freshener.
but he still asks;
"...would you like to buy some fuel injector..."
to which i cut him off and reply;
"HELL NO! i buy that stuff by the gallon!"