I just got back from a 3000+ mile Smokey Mountains and beyond vacation, so now my 03 H. O. six speed w/ 373 rear gear has about 4k miles on it. Before I left I had installed one of Dave Meheen's TAG units on the turbo charger inlet and an Areoturbine exhaust extracter along with a Afe drop in air filter. I drilled 4, 1" holes in the front of the air box for the cold ram air effect but other than these my truck is stock. I pulled a 12k lb 5 er all the way and was amased at how strong this truck is and the fact that there is very little "as in hardly any" soot on my bumper or the trailer. My 01 used to leave a big cloud of black smoke after each take off and I was constantly having to scrub the bumper and everything behind me all of the time but this 03 truck is totally different. There ain't no smoke comming out of this thing and the power was just great, especially in the Smokey Mountains, Hey! I didn't add any smoke to em Ha Ha! Is any body else noticing that there is no smoke comming out of these trucks? I always thought that smoke meant power but I got moocho power without hardly any smoke. Whats the deal her?:--) What do ya'll think is this normal? Billy & Jackie Adams