The OBS Ford trucks are a great choice. I might be biased cause I own and run one but it’s the truth. My 96 F150 runs a 4.9l Inline six that’s legendary for reliability. It’s not very powerful with 150hp but VERY torque rich with 265ft-lbs available at a bit over idle speed. I get a consistent 12mpg city and 15mpg hwy whether I’m towing, have my camper on the back, or if the truck is empty. It doesn’t really seem to care! Be prepared to take your time though as it is not particularly fast. I also have the single cab short bed which affords me a much smaller wheelbase (about the same as a JK Jeep) than the bigger trucks while giving me a bed that’s not only 6.5’ long but also almost 6’ WIDE. Perfect for me to sleep in the back comfortably
The 5.0 and 5.8 V8 options are also great choices with plenty of extra power, but mpg’s drop a bit. The 460 big block V8’s, though nice and very powerful, drink fuel like there’s a whole in the tank. Single digit mpg numbers being the norm.
You could get these trucks with a variety of transmission choices. My truck runs a E4OD 4-speed automatic which is basically a C6 3-speed with an overdrive and electric controls. These autos were shared along the whole lineup, but the 5.8’s and Diesels got slightly better internals. Though this holds true to any automatic transmission, these Ford units really benefit from having a trans cooler installed as heat is their #1 killer. Besides that, keep the right amount of fluid in them and they are pretty bulletproof.
They also came with a 5-speed built by Mazda or one by ZF. The ZF box was much stronger than the Mazda unit which was prone to failure if pushed hard ( severe offroad, big tires, etc.) and was only found on F250-350 models.
The 4x4 systems in these trucks are pretty robust. The 9th gen trucks started getting the Borg Warner 1356 Magnessium transfer case. It could have been optioned either with a floor shifter (most optimal) or a electric shift push-button option.
If you already run a vintage 4Runner understand the frame and running gear will be even beefier than this even at just an F150, nevermind the 250 and 350 varients.
Parts will be VERY easy to find. Any auto parts store in North America has almost everything you want or would need for these trucks. They literally sold 10’s of millions of these.
Where you really start seeing the cons is, well they are old trucks. The rides can be rougher than modern vehicles and NVH levels are pretty high. Things like door seals, hinges, seat foam, and insulation start wearing out over time. This can lead to a much louder and uncomfortable ride than a modern vehicle. Steering on these can be scary loose until your literally replace THE ENTIRE steering system. Still, all these things are easily fixed with some research and elbow grease.
Also, being old trucks, and as reliable a they once were, they are still old trucks. I find that if you’re able to bite the bullet and get everything mechanical straightened out all at once you can get to enjoying them faster. Most need a tune up and a few seals changed.
This is just some of the information and experience I’ve gathered in running one of these trucks for the past 5 years.
Good luck on your hunt!