Discussion Starter · #1 ·
I took a trip from Virginia to the Mississippi coast last week. My outfit is a stock '05 CC, SB with a topper pulling a 16' enclosed trailer. My gross weight was 13,700 lbs. Before the trip I turned 3000 miles and serviced my unit. Rotella t 15w40, fuel filter, synthetic in both axles, Allison spin on and tire rotation. Tires were gauged to the max on truck and trailer. Speed was set with the cruse. Mileage was hand calculated and I must say the lieometer was within tenths on the mileage and amount of fuel used. Ten tanks of fuel were burned on this trip. Mileage was also checked with the tow mode on and with the tow mode off. At 75 mph mileage was from 9.94 to 10.31. At 85 mph mileage was from 8.17 to 8.48. Yes I know this was running hard. Ok here is the kicker the other trucks a Ford 6.0, a Ford 7.3 and a new Dodge Cummins each got 4 or more mpg better than mine at each fuel stop. These trucks were also stock. Each of these trucks were pulling enclosed trailers of about the same weight. Mileage was consistant so I don't think winter blend was ever used. Idle time was not an issue. Am I crazy to expect better mileage? Everyone expected my outfit to get the best mileage. Between the poor mileage and the quart size tank my DMAX was sucking hind tit. Is this the best it will get? Should I try the newest flash available? I don't have any of the problems of the earlier models, surging, overheating etc. I go out west to hunt a couple of times a year and will be needing a bigger tank for sure. Any advise is appreciated....