I believe they changed quite a bit in 07 when they changed the body style up. I've never been under the hood of the latter body style. The 05 was a fist body style still. I was quite jealous when they offered the V8 in the newer ones.
Yep, also sometimes wished for a V8, but V6 was only option in 2002 when I bought my DealerDemo 2001 SportTracJob2;
was really wanting an F150, but they wouldn't fit in my garage & wasn't keeping a new vehicle outside thru RockyMtn blizzards.
Initially had 10kMiles on the clock, still holding its own with original Engine+Tranny at 250kMiles.
Definite weaknesses+quirks, but has suited my needs, proved worthy with good maintainence & relatively minor reliability upgrades.
Early 2001 SportTracs (Job1) of course had the 4.0L~SOHC & old variable IntakeManifold shaped like a pretzel; lots of initial issues.
Later 2001 SportTracs (Job2) again had V6~4.0L~SOHC with new IntakeManifold+ValveCovers+MetricOilFilter, moved OilStick to left & OilFill to right.
2002~2003 SportTracs still basicly Job2s with some improvements: better TimingTensioners, DiscBrakes replaced rear DrumBrakes.
2004~2005 SportTracs still had same 4.0L~SOHC Block & 5r55e Tranny, but many changes: new HybridElectronicControl\HEC PCM+Cluster+Harness+...
2006 model year got skipped, assuming to retool the Louisville KY assembly plant.
2007~2010 SportTracs as you noted had V6~4.0L~SOHC or V8~
5.0L 4.6L , new version of 5r55 Tranny without DipStick, new Frame+Body,+Interior...