I got my 5500 from Dave smith, very happy with it, I "Believed"? I saved apx $5k
Got the turbo, Asine trans, 410. I chose the middle gearing for an average of pulling. I don't go much over 63 or 67mph so didn't need the higher gearing although mileage runs from a low 8.5 (camper & towing light open trailer) to a high of 12 unloaded., not happy about that, but it is what it is...
Like the truck a lot but having to watch the fuel and Ded, heheh can be a PITA at times...
I'd recommend Dave Smith's they will pick you up at the airport on a signed deal. They do get a little rushed at times, so it's not real high on staying with you... but the savings compensated I feel....
fun.