Available in three-quarter-ton (designated 2500) and one-ton (3500) models, the heavy duty variants of the 2009 Dodge Ram are equipped for serious work-oriented towing and hauling needs. Standard on all 2500 trims is a 5.7L V8 Hemi engine with 383 horsepower and 400 pound-feet of torque, which is mated to a 5-speed automatic transmission. Standard on the 3500 trims is a 6.7L Cummins turbo-diesel inline 6-cylinder engine with 350 horsepower and 650 pound-feet of low-rev torque--ideal for towing the heaviest loads--which is mated to a 6-speed manual or 6-speed automatic transmission. The Cummins turbo-diesel engine incorporates a number of technologies to improve fuel efficiency and emissions, including a cooled exhaust gas recirculation (EGR) system, a variable-geometry turbocharger, self-cleaning particulate filter, and oxidation catalyst. The engine is available as an option on all 2500 trims. These heavy duty trucks come with rear-wheel drive or with two 4-wheel drive transfer cases. Two-wheel drive Rams for 2009 again have an independent, double-wishbone front suspension, while 4-wheel-drive models get a rigid-beam front axle. In back, there's a heavy-duty solid axle, along with a Hotchkiss design that includes leaf springs for stability during heavy-hauling. The 2500 and 3500 trims come in single (regular) cab, Quad Cab, or Mega Cab styles, with short (6.3 ft) and long box (8.2 ft) variants. The Quad Cab's back doors have roll-down windows and open 85 degrees to the optional 60/40-split folding rear seats. The Mega Cab model is geared toward rear-seat comfort, offering as much space in back as large SUVs. The Mega Cab's rear seats recline, fold down, and slide forward for flexibility. The top-line Laramie trim is available for both the 2500 and 3500. The 3500 models come with dual rear wheels for increased stability while carrying heavy loads, and have a fully boxed, hydro-formed frame for superior load-bearing. Standard features for the 2500 include keyless entry, daytime running headlights, full-size spare tire and AM/FM/CD stereo. Front and side airbags come standard on the Ram 3500, as do anti-lock 4-wheel disc brakes. Major options include side supplemental air bags, leather-trimmed bucket seats, navigation system, power-adjustable pedals, rear-seat DVD entertainment system (Quad Cab), a power-sliding rear window and the UConnect hands-free communication interface. Available exterior colors include variations of red, blue, gray, brown, black and white.