When was the timing belt changed, if never I would have that done and the water pump while its all apart. All fluids should really be changed. Have you done brakes, did you completely bleed the system? Coolant should certainly be changed as well as the diffs, xfer case, if 4wd of course, and tranny. You could easily change the diffs and xfer yourself, no harder than an oil change, same goes for a manual tranny. You could do the auto but I would take it to a shop and have it flushed w/ the machine. Check your belts and hoses and replace what looks worn. Lube up the driveshaft, new air filter and pcv. Plugs and wires are a good idea as well. Maybe even new shocks if they are still original.