1. Home
  2. Ram
  3. Chassis Cab

2018 Chassis Cab

The Ram Chassis Cab is aimed at customers who want to outfit the rugged Ram Heavy Duty with a custom bed or storage compartment in place of the standard pickup bed. Available only as a "dualie" with four rear wheels, the Chassis Cab comes in a dizzying array of trim, cab and wheelbase configurations. As with the brand's other Heavy Duty models, the Chassis Cab was comprehensively updated for the latest model year with a redesigned frame, cushier interior, new technology features, more powerful diesel motors and more.


Ram comprehensively redesigned the big truck's ladder frame with high-strength 50 KSI steel, including eight separate cross-members, hydroformed main rails and fully boxed rear rails. The changes add up to a stronger, more mass-efficient foundation that helps the truck achieve its best-in-class towing and payload figures.

The suspension was engineered to provide greater roll stiffness for more confident, planted handling in turns. The basic layout continues to be an independent front suspension with coil springs and a Hotchkiss rear suspension with a rugged live rear axle. Further improving driving dynamics is a new reciprocating ball steering system that provides better on-center feel.

The primary engine for the Chassis Cab is the venerable 6.7-liter Cummins turbo diesel inline-six. This mill comes in two tunes: a 320 horsepower, 650 lb-ft of torque version that pairs with a six-speed manual, and a 325 horsepower, 750 lb-ft of torque variant that shifts through a six-speed automatic. All models come standard with diesel power except the 3500, which gets a standard Hemi V8 with the oil-burner as an option. The Hemi is a 5.7-liter unit with 383 horsepower and 400 lb-ft. of torque mated exclusively to a six-speed automatic.

Rear-wheel-drive is standard on the Chassis Cab, while four-wheel-drive can be specified as an option.

Improved Interior

While the latest Chassis Cab features several fresh exterior elements, including revised headlights and a restyled grille, there are more significant changes to be found inside.

The same basic cabin design remains but some materials are upgraded, while new color themes are present throughout. More soft touch materials have been spread throughout the truck's cabin, and the HVAC and multimedia controls are all-new.

Like some of Chrysler's other products, Rams gain access to the automaker's 8.4-inch Uconnect touch-screen infotainment system, which slots into a new center stack with revised climate controls. Ram's gauge cluster receives a more widely-available, upgraded 3.5 or 7-inch (depending on trim level) information screen. HD radio is now included on Uconnect-equipped Rams and a Sprint-powered wireless system is available for buyers who need to remain connected. A proximity key system is newly available, as are Ram Box storage bins that can be locked and unlocked remotely.

Bodystyles, Capabilities and Trim Levels

The Chassis Cab comes in three service levels, including the 3500, 4500 and 5500, all of which can be had in two-door Regular Cab form or as the four-door Crew Cab. Wheelbase options are wide-ranging: the 3500 Regular Cab comes in 143.5 and 167.5 inch lengths with the Crew Cab checking in at 172.4 inches; the 4500 and 5500 Regular Cabs can be had in 144.5, 168.5, 192.5 and 204.5 inch wheelbases, while the Crew Cab for both offers the option of a 173.4 or 197.4 inch wheelbase.

Properly equipped, the 3500, 4500 and 5500 models can tow 22,750, 24,650 and 29,600 pounds, respectively.

Trim levels include basic Tradesman, mid-grade SLT and, on Crew Cabs, the luxurious Laramie. For the 3500, ST includes little more than A/C, power windows and locks, 17-inch steel wheels and a limited slip rear differential, while stepping up to the SLT trim level brings SIRIUS satellite radio, an electronic vehicle information center (EVIC) and 17-inch chrome clad steel wheels.

Laramie models coddle with chrome folding trailer tow mirrors w/ heat, integrated turn signals & puddle lamps, an electric shift transfer case for four wheel drive, the limited-slip rear differential, quad headlamps,17-Inch Polished Forged Aluminum Wheels, heated steering wheel, leather trimmed seating with heating and available ventilation, (EVIC), Uconnect Multimedia System and SIRIUS Satellite Radio.

In the 4500 and 5500, the Tradesman trim includes an integrated exhaust brake for towing, folding trailer tow mirrors, 19.5 inch Argent steel wheels, the limited slip rear dif and EVIC. SLT nets SIRIUS. The Laramie for both models includes full power seats with power lumbar adjustment and automatic dual-temperature controls in addition to all the features standard on the 3500 Laramie.

Uconnect Access

Chassis Cab models are also now available with Chrysler's Uconnect system (for a complete description of Uconnect Access, check out Leftlane's Spotlight On: Uconnect in-depth article). Generally regarded as one of the more user-friendly infotainment setups on the market, Uconnect integrates most of the truck's audio, navigation and climate control functions into one unit.

An 8.4-inch touchscreen mounted on the dashboard is the central component of the system, but redundant buttons and knobs for climate and audio volume and tuning are also included. A newer feature offered on these models is a switchable rear camera display for added user control during trickier towing maneuvers.

Uconnect features a voice command system that allows the driver to place phone calls, use the sound system, input navigation destinations and more without taking his or her hands off the wheel. Other notable aspects of the system include the ability to function as a Wi-Fi hotspot over a 3G network - for an additional monthly fee - and downloadable applications such as Bing search.

Occupant Safety

All Chassis Cab models come equipped with dual front, front side and full-length side curtain airbags in addition to traction and stability control systems.

Key competitors

Ram's biggest competition comes from Ford's fleet offerings, in this case the Ford F-250 Super Duty, F-350 Super Duty and F-450 Super Duty F-450, along with GM's Chevrolet Silverado 2500HD and Silverado 3500HD and GMC Sierra 2500HD and Sierra 3500HD.