I get 16.5 in the city, and 24 highway. On stock size BFG AT KO2s, at 70mph. I like all of the 6 cylinders to be working all the time and, I get PT 4WD.
That said, how many first generation Tahoes, circa 1992, do you still see on the road? Few, if any. Where I live, I see 1st and 2nd Gen 4Rs...