now while it might be a bit expensive, any box that adds power to the engine with the cummins will also add fuel economy if left in the lower settings. this is due to an altered and advanceed timeing and duration giving a more complete burn while useing less fuel to give the same power.

however it is hard to switch them off the higher settings since they add up to 140 asphalt shearing hp

 

'04 QC 4x4 with Hemi = 15.1mpg at 72mph

 

2005 QC 4x4 1500 4.7 auto. 1600 miles on it. averaging 15 mpg so far. Back roads in the hills and some freewaywith ac on.

 

'03 1500 Quad Cab. 5.9 (360) 3.93 gears, Volant Cold Air Intake, Superchips Programer.....15.5 city, 18 Highway (depending on weight of right foot)

 

I just returned from a 1600+ mile trip in my new truck. It had just over 300 miles on the odo when I started out. The truck is an '05 hemi 1500 ST, regular cab with tow package, and 3.92 limited-slip... basically no other options to add weight and complexity. For the last 600 miles of the trip I was towing a new aluminum 16' car hauler (empty) that weighs about 1500 pounds using regular mode (not tow/haul). I consistently (except for occasional construction) drove 72mph with cruise control. Also, one passenger.

I got between 15 and 17 miles/gallon. Interestingly (and surprisingly, at least to me), it didn't appear to matter what the terrain, altitude, or if I had the trailer attached. The best mileage seemed to be under the least likely conditions and vice-versa. Inconsistencies in different pump fill-up "kick-offs" might have accounted for some differences since I never "top off."

Also, I always used middle grade octane gas from "name brand" stations.

All the best.

Oh, forgot to add that it has a Peragon bed-cover that would affect results to some degree. Sorry, about that.

Update as of July 30, 05... city only driving=10mpg.

[IMG]local://upfiles/14944/23B09FBAD0A7465694B8FD2AF30D9008.jpg[/IMG]

 

05 RAM QC Hemi 4kmiles. 14.5 city 19.2 freeway.

 

is that a hemi 4x4? getting ready to buy an 05 hemi with 4" suspension lift, CAI, and exhaust system.

 

Rallyd69:

What is your axle-ratio and highway driving speed, please?

Thanks.

 

14.5 mpg average for the last 5 trips (about 700 miles) with the cummins, towing with a gvw of 20,000 lbs.

 

2002 5.7L 13.3mpg

Wife kills me each time I take it out now. $2.21/g here in NJ.