My '03 common rail ISBe 5.9L Cummins was fairly quiet as far as the clatter goes but you can't get away from the Cummins hum. The 2001.5 with NV5600 and 3.55 Dana 80 rear gear was the most relaxed sounding Cummins Ram to drive. When Chrysler went back to the Getrag trans, AAM rear axle and hydroformed (tuning fork) chassis, it ruined the feel of the truck and took a step back in longevity. Had to have the rear end rebuilt in both my '03 and '05 2500HD Rams before 100k miles. Ball joints in the '05 at 97k miles. Both had the dreaded driveline vibe that the dealer and Chrysler gave up on. A/C evaporators sit in their own muck due to the design of the evaporator housing. So far at 94k miles, my current truck has needed cab mounts and a brake caliper bracket. My hat's off to the Chrysler Hemi engine though.