First Drive GM's New HDS
FIRSTDRIVE
Towing Road Test: 2011 CHEVY SILVERADO and GMC Sierra 2500HD and 3500HD
By Larry Walton
HDS
NEW
GM’s
afety First” is not just a slogan for many contractors, it’s a way of life. If you’re the guy who insists on hard hats, safety glasses and ear protection, you are likely to be concerned about safe driving for your family and your employees as well. Safety while towing big trailers is the biggest benefit I see to the combination of changes GM made to their heavy-duty pickup lineup. Chevy Silverado and GMC Sierra 2500HD/3500HD just got more power, stronger frames, bigger brakes, a diesel exhaust brake and trailer sway control —enough to make safety conscious pickup owners sit up and take notice. I drove the new GMs while towing a variety of trailers in Pennsylvania, Maryland and West Virginia. The Duramax-Allison combo continued to prove itself pulling long, steep grades. It was coming back down those hills, however, where the Silverado and Sierra impressed.
“S
Allison transmission via computer provided one of the best features of the new 2011 HDs: a highly integrated exhaust brake system. Combined with the grade brake and cruise grade braking features that have been in place for several years, the new exhaust brake greatly improves safety for steep country hauling. The new, driver-selectable feature uses the compression power of the 6.6L Duramax engine to improve vehicle control and reduce brake pad wear. When the exhaust brake is engaged in cruise mode, exhaust cruise grade braking will help the cruise control system maintain the desired vehicle speed when travelling downhill, keeping the driver from having to apply the brakes and exit cruise control to maintain speed. When the exhaust brake is engaged in non-cruise mode, the transmission and the exhaust brake deliver the correct amount of braking to assist in vehicle control, regardless of vehicle load. The engagement of the system is smooth and quiet, but I knew it was working. In fact, I hardly had to touch the brake pedal in many downhill towing situations over the two days of testing in the Mason-Dixon line hill country. Since the exhaust brake system was working so well, I knew I had plenty of vehicle brakes when needed.
BIGGER BRAKES
The revamped brakes, those on GM’s new HDs deliver smoother, more immediate and confident-feeling performance. Four-wheel, four-channel ABS comes standard on all single-rear-wheel models and a three-channel system is standard on dual-rear-wheel models. The larger diameter (14-inch) and width of the front and rear rotors support their increased capacity, weight ratings and trailer tow
EXHAUSTIVE RESEARCH
The coordination of the turbo charger, Duramax diesel engine and
18 PRO PICKUP SUMMER 2010