Please consider newer. Look for trucks with R134a refrigerant.

Ford triton engines are known to have spark plug issues that require head thread repair. 5.4L worse.

I’d say Hotchkiss drive. Simple, robust, and reliable.

I'm not a GM guy but the 2000-2005 era I would put GM on top when it comes to powertrain. The 4.3 V6, the 4.8, 5.3 and 6.0 V8s were excellent.

Ford's only good motor was the 4.6 V8. The 5.4 2V V8 was ok, prone to blow out spark plugs. The 5.4 3V v8 was absolutely horrible. The V10 also blew out spark plugs.

The Toyotas were fine with the 4.7 but rusted out even faster than the american trucks.

Dodge had good motors (5.2 and 5.9) but horrible transmissions.

Start with a 3/4 or 1 ton of your favorite brand. Add the base engine and automatic trans, skip the 4x4 option.

Everyone has a problem area, just research your candidate. Hell it might well have been addressed already. Ford, 3valve triton , Dodge transmissions, Chevy, cylinder deactivation and rust.

Perfect world I’d find a 3/4t Ford with a 300 I6 fuel injected. Spent its winters down in Fla parked next to a boat, summers in MI parked next to the very same boat.

3800 was never used in any truck platform by GM.

I had a 5.3l Silverado with 250,000 miles on it.
The engine was fantastic with no issues.
Things to look for if you are looking at one:
Tensioner pully.
Power steering cooler.
Transmission lines. Brake lines. Gas lines.
U joints
Rear leaf spring shackles
Just plain old rot