360,000 miles on a 1987 F-150, with the 300-6.
I had a 1987 F-150. First year for fuel injection on the 300cid 6. Five years and the paint came off on the hood, fenders, and top. Ford Repainted it. at 100K they told me the Oxygen sensor was bad it needed to be replaced, they told me that every year when I got my emissions test. I never replaced it, it passed emissions test just fine without it, and ran just fine as well. Every two years I replaced the starter. That truck eat starters. At 200K replaced the seals in the engine, and had the first tune-up done. They were unable to get the oxygen sensor out, so I told them to forget it. At 250K replaced the Alternator, and water pump. At 360K the transmission started acting up. My son pointed out rebuilding the transmission was $1,400.00 but the truck was only worth $800.00. I put it up for sale. The guy that bought it was amaized the body was in almost perfect condition, no scratches or dings from parking lots. I always park out in the back of parking lots.
Guy bought it for his teenage son. He found out the tranny problem was a leak between the transmission cooler and the radiator, leaking anti-freeze into the transmission. He replaced the radiator and serviced the transmission and everything worked again. A month later I saw the truck had either been rear-ended, or backed into something hard. Next time I saw it the front end was all messed up. Saw it a few months later sitting on the side of the highway, the drivers side was all caved in. The kid never made it to snowfall. He ruined the truck all in the summer time when the roads were clear. Have not seen the old gray truck since, guess it made it to a wrecking yard somewhere. I know there was and still is a high demand for that engine. Easily rebuilt and last forever.
Oh Yea, I forgot I did replace the bench seat twice. The springs broke down over the years on the drivers side.