Assuming is the 5.4, The engine is a hoss. I have one, 2000 extended cab 4x2, short bed. Pulls the 7500 race car trailer easily. It's like a diesel as far as low end torque but it suffers from 4000 RPM+. Fine with me. I rarely need to go more than about 3000 anyway, it just pulls great at lower RPM's. You'll be happy with it.
MPG is typically in the low 19 range on the highway. About 16 in town, stop & go. I don't check it much.
Only issues were spark plug threads. I've never had a problem in 396,700 miles, and I change the plugs about every 50k. Manuals say to change them at 100k intervals, but in my experience, at 100k the plugs are GONE, so when you change them at 100k, replace the coils too. All 8 of them. The plug gap at 100k is about .150", which is hard on the coils, usually get a code for misfire when the coil is bad, plus a bucking sensation under medium acceleration/load.
Also sometimes the IAC will stick. Replace it if it does, typical symptom is a REALLY low idle in gear, hard to start unless you use the throttle, sometimes dies when coming to a stop.
They are GOOD trucks and that engine beats the snot out of the GM counterpart, at least in it's low end torque. The GM 5.3 will destroy it in a drag race because it's power is made up higher in the RPM's.
The 4.6 wasn't as impressive, but still way better than the 4.8 GM, and since it's basically the same as the 4.6 Mustang (2 valve), there's plenty that can be done with it. 5.4 is just a taller 4.6 with a longer stroke, and is a close relative to the Navigator 5.4, which is almost a twin to the 5.4's in the hotrod Mustangs....
Seen reference to your work truck (4.2L V6). Had one in '97, brand new, gutless powerless loud engine. It was "supposed" to "replace" the 300 inch inline 6, but all it did was make more noise and use more fuel while making LESS power and torque. Got rid of it ASAP, went back to a New on the lot '96 with a big six, pulled a bone head move and ran a stick through the lower radiator hose and continued to drive it, overheated it, broke the head, and traded it on the 2000. I love the 2000, the engine makes the truck for sure. The newer trucks just don't have the same low end grunt as the little 5.4 does. I honestly think it pulls every bit as good as my 7.3 diesel does.
