If you’re going through tight spots in the woods, then a compact pickup is the way to go. They fit through areas that the fullsizes can’t get to without getting too beat up.

If you’re doing desert driving or serious mudding, then the way to go would be a fullsize, as they can be upgraded to higher performance needed to move the extra large tires for mudding or the speed for driving across deep sand.

Since you’re going to be adding parts anyways, then it doesn’t really matter which one you start out with, as you can add essential parts like locking differentials, suspension lift kits, performance intake and exhaust, and larger tires to any truck. You just have to know where to look.

Also, when picking out a truck for off-roading, make sure it has a true 4-Wheel Drive system, with high and low range gearing. While this mostly pertains to SUVs, Ford and GMC have offered All-Wheel Drive on their fullsize trucks in the past, and it’s nowhere near as good as true 4-Wheel Drive.

For compacts, look for one of these models from the 1990s and early 2000s:

Chevrolet Colorado
Chevrolet S-10
Dodge Dakota
Ford Ranger
GMC Canyon
GMC Sonoma
Isuzu Hombre
Isuzu Pup
Mazda B-Series
Nissan Hardbody
Nissan Frontier
Toyota Hilux (a.k.a Pickup)
Toyota Tacoma

If you prefer a fullsize truck, look for one of these models from the same era:

Chevrolet K-Series
Chevrolet Silverado
Dodge Ram
Ford F-Series
GMC Sierra
Nissan Titan
Toyota T100
Toyota Tundra

The only truck I actually suggest you avoid is the Honda Ridgeline, which doesn’t offer a true 4-Wheel Drive system, but instead makes do with All-Wheel Drive, which isn’t really suited for most off-road situations.

Off-road parts I would recommend are these:

Limited Slip Differentials – These are mechanical differentials that will make it so you spin all four wheels at once, instead of one front wheel and one rear wheel like a stock 4-Wheel Drive system. Most manufacturers offered these as an option on their trucks when new.

Suspension Lift Kit – This allows the truck to get the clearance needed to get over obstacles and to fit larger tires. I would avoid body lift kits, as they don’t really do much besides allow for larger tires, but leave the frame hanging down to catch on stuff and expose parts that will rust faster.

Performance Intake and Exhaust – More power, better sound.

Brush Guards – Useful when you come around a corner and run through a partially downed tree. Will save you a lot of scrapes on the paint and give a useful place to mount a winch and foglights.

Winch – For when you eventually get stuck, and believe me, you will.

Foglights – For nighttime, and essential for driving in thick snow and fog with a lifted vehicle. Mount these low to cut underneath to see the road.

I hope this has answered your question. If you have any more, please feel free to ask.