2012 GMC Sierra HD Performance
The GMC Sierra 2500HD and 3500HD come standard with a 6.0-liter gas-powered V8 that reviewers like. But reviewers drool over the 6.6-liter Duramax turbodiesel V8, which gets good fuel economy for a heavy-duty pickup and helps the Sierra HD trucks reach their full towing and hauling potential. While the Ford Super Duty trucks can out-tow the Sierra HD series, reviewers say both Sierras are surprisingly comfortable to drive, and are more maneuverable than Ford or Ram trucks.
- “Sierra HDs are surprisingly pleasant and manageable for such large, hefty vehicles.” -- Consumer Guide
- "What amazed me most is how quiet, smooth riding, and generally enjoyable this dual-rear-tired pickup has become.” -- Automobile Magazine (2011)
- "Put wheel-to-wheel against its rivals, the 2012 GMC Sierra 2500HD (and Chevy Silverado twin) can't quite match the Ford F-250 Super Duty in terms of all-out hauling and towing capacities, nor match the Ram 2500 in terms of upscale cabin ambience (in lower trim levels, anyway). But the GMC boasts the best all-around performance and feels the most composed while towing a very heavy load, thanks to its more precise steering and arrow-straight tracking.” -- Edmunds
- "Specs, shmecs—what are these beasts like on the road? For one, they're surprisingly civilized, especially for anyone with experience in similar rough-and-ready trucks as recent as two generations ago.” -- Popular Mechanics (2011)
Acceleration and Power:
Both the Sierra 2500HD and 3500HD are available with either a gas-powered or turbodiesel V8 engine. The 6.0-liter gas-powered engine comes standard on both models, and makes 360 horsepower and 380 pound-feet of torque. Upgrading to the Duramax 6.6-liter turbodiesel V8 in either model will add 397 horsepower and an impressive 765 pound-feet of torque into the mix. Keep in mind that even though reviewers found the gas-powered V8 to be adequate for most tasks, the diesel is better for towing and usually gets better gas mileage.
The EPA doesn’t rate heavy-duty work vehicles for fuel economy, but reviewers expect the diesel engine to get better mileage than the gas-powered engine. With a 36-gallon tank, these trucks are always going to be expensive to fill up no matter which engine you choose. The Sierra HD’s diesel engine can drive 680 miles on a full tank, which averages out to about 18.9 miles per gallon on the highway. Still, such a huge gas tank means that it will cost you a lot of money every time you fill up, no matter what prices at the pump are like.
- "Either engine provides confident acceleration in both around-town and highway driving. … Automatic transmissions are smooth and quick to kick down for more power.” -- Consumer Guide
- "The small-block V8 engine has the roar that we've come to know and love since time immemorial. Considering how quiet the rest of the truck is, the engine sound actually seems almost of out place, but we're not going to complain.” -- Autoblog (2011)
- “[The diesel engine’s] massive (segment-best) 765 pound-feet of torque got that hefty rig rolling with ease, and its (segment-best) 397 hard-muscled horses kept it moving surprisingly smoothly and quietly.” – Kelley Blue Book (2011)
- "The pushrod 6.0-liter V-8 performs well in the HD pickup. While we couldn’t merge onto the freeway as quickly as with the Duramax, we still had plenty of power to get the truck up to highway speed.” -- PickupTrucks.com (2011)
Handling and Braking
Reviewers say the GMC Sierra HD rides and handles pretty well for such a big truck. Most are pleased with the brakes and the exhaust brake, although test drivers don’t agree on the steering. Some say it’s well-weighted, while others think it’s too light.
- "When stacked up against the Ford F-250 and the Ram 2500, the GMC 2500 has a few clear advantages. Superior steering precision compared to the Ford and a smaller turning circle than either rival are readily apparent and appreciated in everyday driving.” -- Edmunds
- “Straight-line stability is excellent, though Sierra's significant size and weight limit cornering speed, as does the expected big-truck body lean. Steering is well-weighted, direct, and responsive. The brakes furnish stable, relatively short stops with fine pedal feel.” -- Consumer Guide
- "Later, in back-to-back comparisons with the latest Ford and Dodge competitors, both the GMC Sierra and Chevy Silverado HD trucks provided the best sense of full control of steering and also brake modulation on winding roads through the mountains.” -- Popular Mechanics (2011)
- "Our only complaint was that the effort felt a bit light at low speeds, but it firmed up nicely at higher velocities.” -- Autoblog (2011)
Towing and Hauling
The GMC Sierra 2500HD, when properly configured, can tow up to 17,800 pounds and haul a payload of up to 4,212 pounds. The 3500HD can carry even more, with a maximum tow rating of up to 23,000 pounds and a maximum payload capacity of 7,215 pounds. The base Sierra 2500 HD can tow up to 10,200 pounds and haul up to 4,212 pounds. To see the amount that a particular model can tow or haul, see the 2012 GMC Sierra HD specs.
Overall, the Sierra 2500 HD and 3500 HD can out-tow and out-haul competing models of the Ford F-250 and F-350 Super Duty and the Ram 2500HD and 3500HD. However, the Ford F-450 Super Duty can tow as much as 24,500 pounds, making it the model to choose if you need maximum towing capacity. Despite the fact that the Sierra HD is beaten by the F-450, which a model that’s not exactly its equivalent, reviewers still say the GMC is one of the best tow vehicles on the market.
- "Both engines haul light loads with ease, but the diesel gets our nod for towing and heavy hauling thanks to its massive 765 pound-feet of torque.” -- Consumer Guide
- "Thanks to its torque-heavy 6.6-liter Duramax turbodiesel V8, we found that towing a 10,000-pound trailer behind the 2012 GMC Sierra 2500 HD truck posed absolutely no challenge whatsoever.” -- Kelley Blue Book
- "Excellent towing manners, plenty of pulling power.” -- Cars.com
- "I employed the GMC Sierra to tow my 19-foot Glastron boat, a burden of only 4,000 pounds. That was a rather piddling load for this well muscled machine and it barely knew a load was in tow.” -- Automobile Magazine
- "Our tow truck was again powered by the diesel, and even with all that mass to drag around, the engine never felt strained, even though our drive route contained several extended grades of seven to eight percent.” -- Autoblog