The 2008 Dodge Ram 4500 and 5500 Chassis Cabs, aimed at the commercial customer, feature numerous class-leading attributes including largest standard fuel tank (52 gallons), largest brake rotors (390 mm), largest caliper pistons (66 mm) and best-in-class first-gear launch for optimum acceleration on vehicle take-off. With industry-standard 34-inch frame rail spacing and flat, clean frame rails on a one-piece C-channel rear-frame rail (50,000-psi steel), upfit-friendliness is a primary theme of the Dodge Ram 4500 and 5500 Chassis Cabs. Showcasing an unrivaled upfit-friendly design that reduces costs for body-builders and customers, all chassis components are below the frame surface assuring easy adaptability and versatility for virtually any upfit application. Offered in dual-rear-wheel models, four cab-axle lengths (60, 84, 108 and 120 inches) are available. The Ram 4500 and 5500 Chassis Cabs will compete within the Class 4 and 5 segments with a gross vehicle weight range of 14,000 to 19,500 lbs. The standard 6.7-liter Cummins High Output Turbo Diesel delivers 305 horsepower and 610 lb.-ft. of torque. The 6.7-liter engine is not only more powerful, it's also cleaner with B5 biodiesel compatibility and a reduction in particulates and nitrogen oxide (NOx) that comply with the 50-state 2007 heavy-duty emission standards. The all-new 2008 Dodge Ram 4500 and 5500 Chassis Cabs offer a six-speed automatic transmission with Power Take Off (PTO) capability or a six-speed manual transmission with PTO capability. An available electronic-shift transfer case is offered and a factory-installed exhaust brake contributes to both safety and superior brake life. Armed with Dodge Ram Heavy Duty's superior suspension system, beefed up even more for commercial applications, Dodge Ram 4500 and 5500 Chassis Cabs provide expanded capability and durability with a commercial-grade chassis mated to a one-piece C-channel rear-frame rail (50,000 psi steel). Four cab-axle lengths (60, 84, 108 and 120 inches) are available. Maximum Gross Vehicle Weight Rating (GVWR) for 4500 models is 16,500. For 5500 models, the maximum GVWR is 19,500 lbs. The Gross Combined Weight Rating (GCWR) for both 4500 and 5500 models is 26,000 lbs. Quad Cab models provide seating for six passengers and are equipped with four standard doors and 60/40 folding rear seats. Demonstrating interior functionality and capability, seat cushions fold up to create a tall storage area from floor to ceiling. An optional floor section under the back seat folds open to form a flat-load floor with additional storage in each of the foot wells. Delivering just as much versatility and flexibility, regular cab models provide generous storage behind the seat and allow for considerable travel use and ease in reclining for both driver and passengers. Safety and security features include energy-absorbing Steering Column, Enhanced Accident Response System (EARS), four-wheel Anti-lock-brake System (ABS), Integrated Remote Keyless Entry Transmitter and Ignition Key, Knee Bolsters, Lower Anchors and Tethers for CHildren (LATCH) and Sentry Key Engine Immobilizer Theft Deterrent System.