HI all,


i cracked open the rear diff case today and i'm letting it drain right now. what should i inspect while i'm in there and what weight oil should i replace it with? it's been whining so i figured i'd take a peak while i was at it. Also what can i clean it with?

thx!

 

Lol...when I read the title, I thought you meant you actually cracked the rear case! That would have been quite a feat.

Anyway, you should check the ring gear and spider gears for wear and fractures/cracks and also check for any metal filing or chunks in the oil. It also wouldn't hurt to pull the driveshaft loose and pull the axle shafts out and spin the carrier to get a feel for the bearings since you said it was making noise.

I use brake cleaner to clean everything! You should replace the oil with 75W-90 GL5 gear oil. If you do a lot of towing or drive really hard, it wouldn't hurt to use 75W-140.

 

^ that was the perfect answer.

 

Use a good sealer when you put the cover back on.

 

Lol I thought about the title after i posted it and realized that was how it sounded :-O

I didnt really have the chance to inspect much because i didn't have a lot of time/jack and stands, etc. I did see a little wear on the ring gear. from what i saw of the spiders they didnt look bad (i didn't see much tho) and the pinion gear didnt seem too bad either. there was a good bit of metal shavings suspended in the gear oil i drained out and some mega sludge on the magnet and everything. I ended up using brake cleaner inside there to clean it up.

The oil change didn't help the sound i was hearing at all, but i didn't think it would be that simple either. I will just roll w it for the time being since i dont have any more money for a lil bit, lol. After the oil change, plugs, PCV, diff oil and a few other things i can't remember atm, this truck is finally running halfway decent. We replaced the NSS too since it was bad and found some troubling stuff in the trans fluid that came out; but thats for another post.