Hey Jeff H, I have a '72 Jimmy that I am slowly (very slowly) trying to restore, great trucks.
Worst of all, no contest - 1990 GMC Suburban. Half ton, 350, auto, 2wd, "conversion package". Velour interior, captain chairs, 2-tone silver/maroon - awesomely sharp looking when we bought it. Ran good for about a year, then the truck started self destructing. EVERYTHING that could fade, peel, split, tear, squeak, rattle, groan, shriek, dissolve, break, or quit did so. Replaced just about everything on it at least once.
The highlight of owning it for me, was driving down a dirt road to the Scout ranch with the usual concert of shrieks, rattles, and groans when BAM!! the overhead console breaks loose from its mounts, swings down onto the light wires and zips over like a pendulum to clock me in the side of the head, almost knocking me out.
Another favorite: 1982 Oldsmobile Brougham - computer and emissions controls by Charles Manson. Car ran like the engine was possessed, vibrated - shook - missed - stalled - ran like a sick puking dog no matter what you did. Spent more time working on it than all my other cars put together. Had a fiendish EGR type system with small pipes running into the exhaust manifolds, these regularly broke and getting them off was an incredible pain. This was the first car I ever actually considered setting on fire just for the pleasure of watching it burn.