Ram's powerful 2500 and 3500 Heavy-Duty (HD) trucks return for 2018 with even more to like. Across the HD range, buyers can choose between gasoline engines in the standard 5.7L and 6.4L Hemi V8s; as well as three versions of the 6.7L Cummins inline 6-cylinder diesel that top the range. All engines include a 6-speed automatic transmission, although a 6-speed manual transmission is offered with the diesel engine. The 5.7L Hemi is rated at 383 horsepower and 400 pound-feet of torque. The 6.4L Hemi V8 makes 410 horsepower and 429 pound-feet of torque. With the 6-speed manual, the Cummins is rated at 350 horsepower and 660 pound-feet of torque at just 1,500 rpm. When mated to the 6-speed automatic transmission, output jumps to 370 horsepower and 800 pound-feet of torque. In Ram 3500 trucks with the top-duty Aisin automatic, it makes 385 horsepower and a staggering 930 pound-feet of torque. High-pressure common-rail fuel injection helps aid refinement and clean up emissions and the Cummins is B20 biodiesel-blend compatible. The 5.7L, meanwhile, can be outfitted from the factory to run on compressed natural gas.

Diesel Rams employ a Ram Active Air intake system that draws more cool air from the front of the truck for more power in hot temperatures or at high altitude. Also thanks to a variable-geometry turbocharger, Ram HD trucks have good responsiveness and drivability no matter what the load.

Ram HDs can be ordered with either rear-wheel drive or 4-wheel drive. In 4-wheel-drive models, a front-axle disconnect system can help improve fuel economy by up to 1 mpg. The Ram 3500 utilizes a Hotchkiss leaf-spring rear suspension, while 2500s have replaced leaf springs with a 5-link coil spring setup. Front suspension is now courtesy of a 3-link system. 2500s can be optioned with heavy-duty air suspension in place of the coil springs, which allow for driver-controlled load-leveling with precise, individual adjustment. Leaf-sprung 3500 dual-rear-wheel trucks with maximum tow packages also feature the air suspension system.

Ram 2500 trucks benefit from an 11.5-inch rear axle, while the high-output Cummins includes an 11.8-inch axle. The result is best-in-class towing and payload ratings for the 3500 (up to 30,000 pounds and 7,320 pounds, respectively) and best-in-class towing for the 2500 -- up to 17,940 pounds. For the first time, Ram offers an optional fifth-wheel tow package.

Ram understands that its trucks must last a lifetime. As a start, the company offers a 5-year, 100,000-mile warranty on all of its powertrains. Each truck also has extended maintenance cycles for fuel filters and oil changes, including a 15,000-mile interval on the Cummins diesel.

Inside, Ram HD trucks have been reconfigured to allow for increased creature comforts. Available amenities include soft-touch instrument panels and door trim, 2-tone upholstery and contrasting stitching. Wood and metal inlays accent the interior and a largest-in-class 8.4-inch full-color touchscreen display serves as central command for the Ram HD. Heated and ventilated seating and a heated steering wheel are also available. Buyers can choose between bucket seats or a 40/20/40 bench configuration. In either case there's a multi-media port in the center with USB, SD and auxiliary inputs.

Eight trim levels are offered: Tradesman, SLT, Big Horn, Laramie, Outdoorsman, Laramie Longhorn, Power Wagon and Laramie Limited. These can be configured with either 2- or 4-wheel drive, 2-door Regular-cab, 4-door Crew-cab or 4-door Mega cabs. Two bed lengths are offered, a 6'4" or 8'. Ram's patented Ram Box can be equipped in several trims, adding a secure storage system in the sides of the bed.

Each Ram HD offers a different set of interior appointments and equipment that can be tailored to fit basic work needs or provide a relatively luxurious cabin. Two different Uconnect systems with the 8.4-inch touchscreen are offered both with Bluetooth hands-free connectivity. The top system also provides wireless Internet connectivity, as well as HD Radio and SiriusXM compatibility.

Top Laramie models offer impressive luxury and convenience, including a power-sliding rear window, leather upholstery, a heated steering wheel, dual-zone temperature control, an overhead console, a universal garage-door opener and special in-floor storage. Available features include an Alpine 10-speaker premium audio system, rain-sensing wipers and projector beam headlamps.

Best-in-class Features Across Multiple Categories

Impressive Powertrain Offerings

Tow Ratings Up To 30,000 Pounds

Luxury Options

Available Uconnect Technology

Excellent Powertrain Warranty

The Ram HD has few changes for 2018, though the big Cummins 6.7L diesel found in the 3500 now produces 930 pound-feet of torque.

Ram 2500 models are intended for the most extreme personal-towing needs, while the 3500 models are aimed at heavy commercial use by ranchers or construction crews. With the diesel model's gains in fuel efficiency, as well as other maintenance-related improvements, running costs should be down versus these trucks' predecessors.

Even compared to the other latest heavy-duty trucks, the Ram 2500 and 3500 HD models have some of the best-appointed, most luxurious and most attractive interiors, picking up much of the look and some of the high-line materials from the latest light-duty Ram trucks.