Original engine had to be replaced at 290,000 miles.
Transmission case cracked and was leaking, so had to get a rebuilt 5spd trans. at about 320,000. Not happy with the RB unit.
Rear end required new axle seals at about 325,000, so I had the bearings replaced as well as upgrading to a Eaton Carbon posi unit. The original "Gov Lock" limited slip unit never failed, which is unusual according to the mechanic.
Wiring for drivers power window failed around 50,000, and the power window motor also needed replacement at 75,000?
I had overheating problems due to bad head gaskets around 150,000? miles, but did the repair myself and had the heads rebuilt since they were off the engine.
Now days I have a terrible time getting quality replacement/rebuilt power steering pumps, steering boxes, clutch master cylinders, transmission, etc. They all seem to need a "do over" or two. Very frustrating.
I drove a 1956 Chevy pickup daily for almost 17 years. When I drove my buddies new 1989 C1500 I knew I had to have one. I had been in the market for a new truck for years, but never drove anything that made me want to sign on the dotted line. After driving my friends truck, I placed a factory order and got one just like his. Almost.
I was a Chevy guy and knew the 5.7 motor was one of the best motors ever made. I also liked the 5 speed manual trans. I've replaced about everything on the truck in the course of normal maintenance. I was disappointed to only get 290,000 before I had to replace the engine. It still ran perfectly, but the oil pressure was almost nil. I could have replaced the oil pump and tried to nurse it along, but it was only a matter of time.
My buddy just sold his old 89 and got the new Toyota Tundra. It's a little too big for me. I'll keep my old truck till I find something I can't live without.
My old truck looks and runs like new. The interior is still in new condition. I did replace the bench seat when the foam packed down and made the driving position uncomfortable. It's very comfortable to drive. I have a nice custom metal canopy to store my work tools (Contractor).
The brakes aren't the most powerful, but adequate. The gas mileage is 14-15 in town and 18 or a little more depending on how fast I drive. My buddy could get a best of 20 with slow driving and a light load.
I have gotten much better service from my truck than many others have reported. I'm pretty mechanically inclined and can spot problems and get them fixed before there is a breakdown. All my stuff lasts almost forever. This includes my work power tools, my motorcycles, sporting gear etc. If you don't take care of your stuff it will fall apart. Of course some things are pieces of crap, and no amount of fussing over will make them last.