Old truck performance report
14.227 mpg over 5,000+ mile trip.
It is my highly biased opinion that the pre emission (2007.5 and earlier) 5.9 Cummins Ram trucks are the best bang for the buck in the older truck market. I was always a big fan of the 7.3 Fords but I do think they come in second to the 5.9 Cummins Ram.
The truck: 2006 Ram 3500 SRW quad cab 2wd auto short bed 5.9 Cummins, 215,000 miles. Transmission rebuilt at 197K just because it was time. Single disk billet torque converter. Original injectors. No tuner or performance mods, only gauges and an exhaust brake.
Towing 2003 25' Airstream Safari loaded to max weight (possibly a tad over). Driving style, 60 to 65 mph, 70 if needed but not often, anticipated stops, easy acceleration unless aggressive is called for. I tend to keep an eye on the pyrometer and try to keep it around 6K if possible.
Trip: Florida to California and back, 5,000+ miles. Fill up at start, log starting mileage, log all fuel stops, fill up at end with fuel added to total and log ending mileage. I do watch the truck's computer while traveling and was surprised to see the variability in mileage shown on this trip. I'm used to seeing it hang around 15 or so but on this trip it was showing low 13s to high 12s initially which had me concerned. Injectors finally giving up the ghost, engine wear, poor fuel, lead foot? I never suspected the computer could be reporting erratically. On the return trip driving fairly late one night the computer gradually went up to, and held, 15.8 mpg. The next mornings driving saw it run back down to 14 for so. It made no sense.
I just returned to home base and calculated my real mileage. 14.227 mpg average. I remain hitched most of the time although the mileage does include a few bob tail trips to get groceries. All in all pretty respectable performance for an old timer. I had calculated an earlier coast to coast trip with a previous AS 25' at closer to 15 mpg, actually 14.75, so this is close enough for the difference to be meaningless.
“While you live, shine / Have no grief at all / Life exists only for a short while / And time demands its toll.”