I had a similar incident happen to me at about 12k. It would bog down when I mashed the accelerator and a lot of smoke. This happened while towing my trailer. When I let off the pedal a little it would pick right up, push hard on the pedal it would bog back down. Max speed on a flat was about 65. Took it in they diagnosed it in about 8hrs. It was the variable turbo vane positioning sensor, they had to send for a new sensor took 2 days, I got it back has run great ever since. I might just be me but it seemed louder after the fix. This is the only problem I have had. 16k on her now. Hope this helps.
Truck was stock when this happened.
Dennis
this
2004.5 2500HD CC/LT/DA 4\" Tuff Country lift, 295/R75/16- on 10\" Centerline Wheels w/caps, AFE Stage II w/ProGuard 7, 4\" MBRP downpipe back exhaust, ICI Wheel to Wheel Nerfs, and a little bit of Get-up-and-GO.<br />2005 Weekend Warrior SuperLite 32\'5er Toy Hauler.<br />2004 Polaris Ranger 6x6. I haul it around to go where the truck won\'t go.