:blahblah: Just wondering if anyone has had issues with low (7-8mpg towing) and low power from their 04.5 or 05 Dmax. Empty the truck (05 Crew cab short bed) has good power and respectable mileage(about 14-17), but hook up our trailer (about 7500 lbs) and it's a dog. I know that the truck won't accelerate pulling like it will empty, but my old 1997 Ford PSD pulled the same trailer as good or better, and had a bit better mileage.

I am running BFG 285's so some power and mileage loss is to be expected. Usually run the Hypertech at level one or stock when pulling and the power and economy don't change that much.

I would like to take it into the dealer and tell 'em to check it out, but I think they will just tell me the tires are too big or I shouldn't have run a chip.

Since I am new to this Duramax thing and all of the computers that it has, Does anyone think I'll have a problem with the dealer knowing that I have run the Hypertech???

Thanks a bunch for all of the great info on this site and any advice you could give would be greatly appreciated.