The Cummins Turbo Diesel comes on 3500 models. It was enlarged to 6.7 liters for 2007, meets 2010 emissions requirements, and has an exhaust brake as standard. The option price is listed at $6,100 but it requires an Ultra Clean Diesel charge of $995, making it about the same price as Ford and GM diesel options. Unlike the GM, the Cummins comes with a six-speed manual, and unlike Ford, the new automatic is a six-speed unit. Neither Ford nor GM offer the exhaust brake that makes intermountain towing stress free; the Cummins does an excellent job of controlling descent speed when wanted, thereby leaving the service brakes cool and free for more immediate stopping.
The vaunted Cummins is an inline six-cylinder built like a tractor-trailer engine, with exceptional longevity and low-end grunt, and it's frequently used in trucks and motorhomes that carry 2-10 times what a Ram pickup will. With the latest injection system, it is very clean (the tailpipe won't even go dark), much quieter (you won't even hear it with the stereo on), more responsive, and more powerful. The Cummins makes 350 hp at 3000 rpm, in the same neighborhood as Ford (350 hp) and GM (365 hp). Torque when paired with the manual gearbox is 610 pound-feet at just 1400 rpm; with the automatic, it's 650 lb-ft at 1500 rpm. Torque is what gets a load in motion, so the Cummins is the obvious choice for towing heavy trailers. The Cummins produces as much torque pulling away from the intersection as the Hemi does when revved to 4000 rpm. Many RVers report better fuel mileage towing 10,000 pounds with their Cummins than a Hemi gets in an empty truck.
The top tow rating with the Hemi is about 11,500 pounds on a 2500 series regular cab. Adding a larger cab or 4WD will reduce the tow rating due to the added weight of the truck. Since Mega Cabs are the heaviest models, they do not carry the highest payload or tow ratings, but our Mega Cab rated 2,681 pounds of payload carrying capacity. The highest payload for a Ram HD is more than 5,000 pounds, the maximum tow rating is nearly 17,000 pounds.