Timing chain became weak stretched last year; replaced that, along with water pump at 218,000 miles.
Replaced heater core and radiator myself right after I bought the car.
Valve covers leak.
Rear main engine seal leaks.
Check engine light comes on and off as it pleases. The car still passes New York emissions.
Car idled rough and ran too fuel-rich at cold starts after I bought it. A few vacuum lines and choke adjustment too care of this.
Typical 1980's GM chicken-feet paint cracking... The car still looks good from a distance.
Replaced worn out rear springs and 4 shocks.
A/C hasn't worked in many years.
It's slow, very slow by today's standards. When I bought it, all 4 shocks were leaking and the rear springs were shot. When I would start it up in the morning, it would shake, jerk and sputter like crazy until the engine warmed up. It still drove like a soft cloud. After a little long-neglected maintenance, I had it running and driving like a new car.
The engine - it's virtually indestructible, durable, surprisingly economical for its era, and has plenty of power for normal driving. That's it. Keep a light foot and you can get upwards of 24 MPG on the highway. City driving will be not be economical, but it's a 3700 lb car with a V8, it's made for the open road.
What a lot of people don't know about the 1985 and newer Oldsmobile 307 V8, it had different cylinder heads than the older models. They have roller valve lifters, but have even punier intake and exhaust ports than the older 1980-1984 models. It runs very smooth, but this engine simply cannot breath good above 3000 RPMs. Even the 1980-1984 models can be modified if you really want to waste the time and effort getting 20 or so extra horses. I've had a 1982 Buick Estate wagon (300 or so pounds heavier) leave me in the dust at a stoplight. My car can barely break the tires loose on wet pavement. Putting faster gears in the back is pointless, it would simply get the car up to the RPM range where it can't breathe sooner.
Sure in 1985 you could get a collectors edition (mine is a base model), but who'd want to collect an even slower car?
With all that said at least GM put some effort, thought and style into designing this thing. I got into an accident with a newer Honda Civic that ran a stop sign. Who says old cars don't have crumple zones, as long as it's the other car :-) I tore the whole front clip off that little car, pushing it teetering off a median and barely bent my bumper.
I believe the only options on this car are power locks, split front bench seat (yes those were optional), A/C, tilt steering, cruise, and a digital readout radio with a tape player. And the tape player still works. No power windows, but at least they aren't duct-taped shut like some of the newer Buicks that have power windows constantly falling off the tracks. The drive train is slow, almost archaic but simple, tried and true, and tough. And I don't have an engine that dumps coolant into my intake due to poor design, like my 1999 Park Avenue did to me.
So even for a Buick it isn't that fancy. But over a quarter century after leaving the assembly line, it still gets a person from point A to point B without many problems. And that says a lot.