Heavy-duty off-road pickup truck sales have become one of the most competitive in business. Ford, Ram, and GM offer trucks that can tow and drive on rugged terrain. The latest Chevy Silverado HD ZR2 and GMC Sierra HD AT4X employ Multimatic DSSV dampers and an independent front suspension. I wanted to chat with Tim Demetrio, engineering group manager at GM, about how race vehicles do this mix. GM HD pickup trucks have had IFS for almost 20 years. Chevy and GMC disagree with the claim that solid axles are easy and durable. When I asked Demetrio why IFS was suitable for a vehicle like the Silverado HD ZR2, he said it rode nicely and stuck to the road. Trucks with solid axles usually give drivers less driving knowledge. GM was ahead of the curve when it prioritized comfort for its most expensive automobiles. Demetrio thinks the Silverado HD’s suspension is sturdy enough for the ZR2 off-road model since it was designed to work. “The cool thing about starting with a heavy-duty platform is that all of the parts are already very well-suited to what we throw at them in the desert,” Demetrio said. “That’s the cool thing about starting with a heavy-duty platform.” The base HD has solid sections for towing and cargo, so we didn’t need to strengthen anything up there. It’s a great foundation. They have cast-iron control arms, robust front suspension joints, heavy-load torsion bars, and plow prep kits. In truth, your off-road damage isn’t as severe as many others’ heavy-duty damage. A truck with a front snow plow should be able to manage high-speed bumps. Contrary to popular belief, the Silverado HD makes a better off-road basis. IFS is also famous for desert racing, although only in lighter settings. Demetrio advises off-roaders, “Look at all the high-performance trucks out there, like a trophy truck with independent front suspension.” Off-roaders with solid front axles are stuck in the 1970s when Jeeps were popular. Only tiny cars have employed Multimatic DSSV dampers. Using open-wheel vehicle technology, Newman-Haas won seven of the 19 CART races in 2002. Since then, Multimatic has offered DSSV systems to several automakers, notably Chevrolet for the Camaro ZL1, Colorado ZR2, and Silverado ZR2. They scale well and work on any rig without any modification. Along with their reliability, this is why makers favor them. “Multimatics have a huge tuning range.” Demetrio called the DSSV the “secret sauce.” Our position-sensitive zones—standard, rebound, and jounce—can be tuned separately. This offers many damping force possibilities. “Even though the weights are different, the damping forces needed for a high-performance midsize off-road truck and our heavy-duty trucks aren’t very different.” Expect a smoother, more flexible, and easier-to-move HD ride. Colorado and Canyon are firmer and livelier. Damping forces are comparable. The HD has higher power, but its bandwidth and operational range are relative to the DSSVs and internals. Colorado ZR2 and Silverado HD springs must be balanced despite their similarities. “The hardware is different,” Demetrio said—packaging matters. The HD has a massive half-shaft and a different front suspension then our light-duty and midsize automobiles. All three cars have identical piston hardware. However, the reservoir packing and damper spool valve location vary. Even though they shut differently, I think they have around 75% of the same parts, with a few packaging modifications. Demetrio mentioned the “secret sauce” when we met. People sometimes think autos should be bigger and more straightforward. Despite genuine objections, calling these rigs “basic” is wrong. Because they have a body on frame and massive tires, they’re versatile. We stopped discussing how difficult it is to construct a high-performance off-road HD automobile. Demetrio concluded: “My team handles all General Motors’ options.” We maintain Blackwings, ZR2s, and AT4Xs. On-road performance is easier to get correct than off-road performance while developing cars. Flat track running is unchanged. Most of them can be made for. However, you must sacrifice off-road features to be good at rock climbing. Off-road is more complicated. Racecars are simpler than trucks. Not an internet jerk but a carmaker. These cars can perform any task on or off the road. Four-wheeling is lovely right now.
