Ran badly when handed down to me - 3-4 mpg, no power. Rebuilt the carburetor, and that was almost like putting a new engine in - much more power, mileage up to 12-13 MPG.
Rebuilt entire brake system (master cylinder, power brake booster, front calipers + rotors, rear pistons + drums) as most of the parts were either leaking or just worn out.
Had to replace the solenoid that switched between the dual gas tanks once.
Had a tendency to run hot in the summer (temp guage would sit at about 3/4) - had original radiator, though.
Steering was extremely loose, but controllable.
Had an appetite for starters - every 6 months I'd have to replace it.
Ford's (in) famous DuraSpark II ignition system - had to replace the control module every 6 months as well (new ones were only $15, always carry a spare if you own a car with this system).
Heater core ruptured around 280k?
Transmission finally went out around 300k.
Engine always leaked LOTS of oil from the rear main seal - running straight 60 weight oil would usually lose a quart every day. 10W30 would empty the oil pan within 30 minutes.
This was my first car, given to me by my dad. Consider the abuse a 16 year old puts a car through - it definitely lived up to "Built Ford Tough".
It still ran "OK" when I sold it - the a/c even still worked! It had been poorly maintained before I got it (but the paint shined like it'd just come off the showroom floor), and it still put up with my abuse.
The engine had been run dry (no oil) twice - and the oil light didn't work. Both times it started knocking and running hot, and both times I pulled over, walked to the nearest store, got 6 quarts of oil, dumped it in, and started it back up. It just refused to die.
The only time it left me stranded is when the original DuraSpark electronic ignition module died while going down the road - I always carried a spare one after that. It still looked brand new inside and out when I sold it, except for 1 very small tear in the side of the bench seat.