For your transfer case oil change, which takes about 1.6 quarts, your oil options are insanely priced Toyota 75W at $80/quart, Ravenol 75W at $20/quart, or, my recommendation; HPL 75W at $16/quart.
Itās not listed here, but if you call them, theyāve got it.
HPL Differential Life gear oil is designed to provide superior operation in a multitude of automotive applications including gear and clutch limited slip. HPL Differential Life is formulated with synthetic base oil and state of the art additive chemistry for maximum performance. This oil is...
www.advlubrication.com
Donāt forget the BITOG15 discount code for 15% off.
The transfer case drain plug is a pain, youāll have to remove a small protective plate. Itās a square drive NPT, so it seals on the threads. I used a couple wraps of blue Teflon tape. Iāve got pipe plug sockets, but I think you can use a 3/8ā extension.
The transmission can be flushed using the cooler line. Pin the thermostat open, disconnect the return line from the cooler, idle, refill, repeat until clear. Youāll need a way to refill from the side of the transmission. Total PITA.
I have a pressurized bottle, like this, that I fill with WS ATF (I used AMSOIL, next fill will be HPL green).
Probably worth doing a pan drop and filter change, too.
Differentials are easy. 75W90. About 7 quarts needed for front and rear.