Computer (SBEC), fuel injectors, oxygen sensor, EGR valve, throttle position sensor, front seal (twice), timing cover gasket, valve cover gaskets, u-joints, harmonic balancer, differential (play in gears), radio, speaker, various trim & moldings, seat position mechanism, seat tilt mechanism, seatbelt retractors and gas cap (incorporated vent).
This was a well maintained one-owner truck when I purchased it. One problem after another. Couldn't trust it enough to go long distances.
I would find my truck to be the opposite although I do have the 3.9L auto ext. cab. I bought the truck with 230,000km on it and in a year and a half it is at 300,000km. The only parts I've replaced are wear and tear things like Tires and brakes.
I've got a 1990 ext cab and nothing has never gone wrong with it guess automatics are more reliable.
I have a 1990 extended cab Dakota also. I got it 2 years ago as my first vehicle. Since then I have put about 30,000 miles on it. I haven't had any major problem with it at all which is surprizing with how I drive, the past two years have been constant abuse. Daily power braking, tire spinning, and hard accelarations haven't seemed to hurt it. It has seen countless neutral drops, donuts, revving into the red, driving through ditches and fields at medium speeds, and been topped out many times as well (105) not best for offroad (2wd) not really fast (3.9 V6) good all around truck, doesn't look bad, has seen hell, but wasnt scared-good machine.