Just got back from a mini-vacation at our "soon to have a house built on it" property in Northern California and am impressed with the overall miles per gallon my 2001 KR 4WD delivered. San Diego, CA to Lake Almanor, CA via a stop over in Reno, NV (both coming from and returning to San Diego) for a total of 1,336 miles. Best was 19.2 mpg with the overall average approx. 17.4 mpg. Route was US 395 (from San Diego to Reno) so speeds varied from the low 20's through towns to just above 90 a few times (mostly 75 to 80 mph) with altitude starting a 326ft finishing at 4,728 ft with the highest point being 8,400 ft.
Prior to the trip I had the oil (5W-20 synthetic) and filter changed and added TriboTech IJP to the oil and TriboTech Spectrum to an empty fuel tank just before filling and TriboTech Accuphase to the transmission. Back in 1991 I first tried TriboTech products in my 1991 Explorer 4dr. (oil, fuel and transmission treatments) and "she" is still going strong at 180K miles on original engine and transmission (treatments every 60,000 miles) - though the paint is in very sorry condition.
Seems that a tonneau cover makes a difference in mpg (along with whatever the TriboTech products did to make the engine perform). Truck performed great for the entire trip. On the long uphills we turned the AC off but kept in on for most of the trip.
While in Reno we got to see some of the early arrivals for the Hot August Nights celebration - a mint '53 Corvette and quite a few classic Ford F-100's and 150's. Many came over to see the KR too.