I just picked up a former work 1998 T-100 SR5 Xtra cab auto 2WD with 307k on it fer $2200. Had to replace all the shocks, clean the MAF/reset the ECU, clean the throttle body/IAC valve, clean the PCV valve. I got 15ish mpg on the highway fer the first tank before I did all my work. Now I'm just over 21mpg on the highway...slowly gitting there.
I believe the previous owner never changed out the original timing belt/water pump. It's the next thing on the list of things to do...
Gonna Auto-RX the engine, transmission, power steering, and differential when my order gits here.