REAR DIFF COVER
Rear differential covers are not only aesthetical pleasing, but they serve a very functional purpose; better cooling. With a larger capacity than stock, in this case 25% more, and cooling fins, after market diff covers help reduce heat in the rear diff, especially under stressful driving conditions, such as those encountered when off road. The added thickness also adds strength to the differential housing.
The product is well made and well finished and feels very solid. The gasket surface is very smooth and the aluminum is 3/8" thick around the gasket flange and 3/16" elsewhere. There is an easy to reach fill plug (level check) and easy to access drain plug. The stock drain plug is in the diff casing and leaves a small amount of oil in the bottom of the diff. This of course is where the sludge and other foreign matter gather and never get drained during routine service. The diff cover drain plug is at the very bottom of the diff, allowing all oil to be drained.
The drain plug is also magnetic, so that it catches any metal particles in the diff, a good way of also checking for potential issues. The drain and fill plugs are galvanized and come with a copper washer. The mounting bolts and washers are all stainless steel.
Full instructions were provided and should be followed, but here's my notes on the installation process.
Removal of stock cover
I didn't bother draining the oil out of the diff, I simply put a large container underneath and started loosening the bolts with a 1/2" socket. Once they were all loose ( 3 or 4 turns, I simply pulled the bottom of the diff cover away from the diff and the oil flowed out into the container. Do make sure the container is there from the beginning, as a small amount of oil will seep out as you loosen the bolts.
You need to "unhook" the bracket at the top, which kind of just pulls away, and then the cover just comes out underneath. Leave the container underneath as the oil will continue to drip out for a while.
The stock gasket appears to be of the reusable variety, however, I opted to go with RTV (red) high temp gasket maker. Double check the diff gasket surface for any oil and then mount the new diff cover, tightening bolts in the usual cross pattern. Once you have tightened all the bolts, go over and check them again, as the first ones to be tightened may become lose as others are tightened.
Finally, fill the diff with 75W-90 synthetic gear oil, remember it will now take more oil to fill now, also do make sure you have the drain plug installed first!
Overall, a very simple install that required minimal tools and was completed in 45 minutes.
Click on the pics below for larger images;
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