When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Found some STP conventional 75w90 for $6.99*6.5%sales tax-10% Mil discount came out to just under $20 for three which is a lot better then $15/QT just to drain out after a tank or two of gas.
Spent two hours in windy 40* weather putting the diff cover in and filling it up. I cleaned all the bolt holes with a tap, installed the cover with a lube locker gasket, installed the fancy magnetic drain plug, and torqued everything to spec only to find that I had no way to fill the diff. . The OEM cover has a Fill/full plug and no drain besides removing the cover completely. The new cover has a drain down at the bottom but no fill port and there’s no fill port on the axle for some stupid reason. I tried filling through the pressure vent but that was so slow it was going to take hours and I wasn’t willing to deal with that down the road.
So I pulled everything off, measured where the OEM fill port is, and drilled and tapped a 12x1.5 hole for a homemade fill port. I debated between 12x1.5 and 12x1.75 threads and settled on 12x1.5 thinking more threads in the 3/8” plate would seal better. Seems obvious until I went to Ace to get a 12x1.5 bolt and found they have every style 12x1.75 bolt I could want and only a small handful of 3” hex head grade 8 12x1.5 bolts I was really hoping for a flange head. Anyway had to take it home cut it shorter so it didn’t have a nub trying to grab the ring gear and then use a die to clean up the threads.
It all worked well and I sealed the fill port with a loctite thread sealer I’ve had good luck with before. Added 3qts and it could probably use a little more but so far so good no leaks.