All of the differential fluids should be changed. Before doing so, get all of the gaskets for the drain and refill plugs from the dealer for the rearend, transfer case, and front differential. Access to the darin and fill plugs is no problem. I use a hand pump that screws onto the oil bottle, 3-4 bucks from Walmart/Pep Boys/etc. I used 85w-90 in everything. You have to drop the front skidplate to get to the front differential. On the front differential, a 10 mm allen wrench fits both the drain and refill plug.
It took me 1 1/2 hours to drain and refill all of the differential fluids.

I changed the fuel filter at 30k. The fuel line is under a lot of pressure, and I didn't loosen the gas cap or follow any of the other procedures to reduce the pressure before removing the fuel filter. I knew that gas would come squirting out of the fittings, so I wore safety glasses and stayed clear. The fittings were on very tight. Use two wrenches (one to hold the filter fitting, the other to loosen the fuel line fitting), and be careful when loosening the fittings so you don't bust your knuckles. When I installed the new OEM filter, it leaked at the fittings, so I had to put teflon tape on the threads.

I squirt grease in all the u-joints every 15k. This became a habit when I owned my 1st Gen. All of the u-joints have zerk fittings, and access to them with a grease gun is no problem.

I like to change the air filter once a year. I think the owners manual recommends 2 years/30k.

Finally, I change the oil and filter every 3k, and rotate the tires every 5k.

wquon
2000 Ltd 4x4 auto tranny, 46k