Overview & Reviews

GMC has long been a mainstay of American byways and highways. Originally used and respected by farmers, construction workers and small-business owners, GMC's hauler was a basic workhorse known for its reliability and longevity. More recent times have seen GMC's full-size truck adopt the name Sierra. And with a variety of body styles, powertrains and trim levels, the Sierra is as adept at serving as the weekday family car.

However, this is the 2500HD version we're talking about. Though "HD" has become a familiar pop-culture concept in recent years, rest assured that the HD part of GMC Sierra 2500HD does not, in fact, involve plasma or LCD TVs. In this case we're talking the old-fashioned meaning of HD: "Heavy Duty." As one of two GMC heavy-duty full-size pickups, the 2500HD is a true workhorse that adds big-league power, towing and hauling capabilities to its family-ready credentials.

Current GMC Sierra 2500HD
The GMC Sierra 2500HD is available in regular, extended or crew cab designs, with a long or short wheelbase, and with rear- or four-wheel drive. The extended and crew cab body styles are offered in four trim levels: Work Truck, SLE, SLT and top-of-the-line Denali. The regular cabin can only be had in Work Truck and SLE trims. Moving up through the ranks obviously adds more style and features, culminating in the top-shelf Denali.

Standard on all Sierra 2500HD pickups is a 6.0-liter V8 that makes 360 horsepower and 380 pound-feet of torque, paired to a six-speed automatic transmission. The burly Duramax 6.6-liter turbodiesel V8 that puts out 397 hp and 765 lb-ft of torque is optional. Its standard Allison six-speed automatic is well suited to towing and hauling large loads.

In a recent comparison test, GM's heavy-duty trucks came out on top thanks to superior all-around performance. Although multigenerational brand loyalty may dictate what heavy-duty pickup you take home, sticking with (or switching to) the GMC Sierra 2500HD would be a solid decision.

Used GMC Sierra 2500HD Models
The present-generation GMC Sierra 3500HD debuted for the 2007 model year. Originally, the 6.0-liter gasoline V8 produced 353 hp and 373 lb-ft of torque, while the 6.6-liter diesel V8 was good for 365 hp and 660 lb-ft. The gasoline engines' current output arrived for 2010.

More changes occurred for 2011 when the Sierra received an all-new frame along with new suspension components (for greater towing capacity and a smoother ride), a more potent turbodiesel engine cranking out 397 hp and 765 lb-ft (previously 365 hp and 660 lb-ft) and the debut of the ultra-plush Denali trim level.

The previous-generation Sierra 2500HD was sold from 2001-'06 and lived on one more year as the "Classic" for 2007. There was a heavy-duty package available for the light-duty Sierra 2500 in 1999 and 2000. That light-duty Sierra 2500 has been discontinued. In terms of updates, there were changes made to the exterior and interior styling for 2003, with further exterior tweaks for 2005. These trucks came in Work Truck (after '03), SL, SLE and SLT trim levels.

The standard engine was a 6.0-liter V8 that made 300 hp and 360 lb-ft of torque. There were two optional engines: an 8.1-liter gasoline V8 producing 340 hp and 455 lb-ft and a 6.6-liter turbodiesel producing 300 hp and 520 lb-ft. This diesel was upgraded in 2006 for more power and refinement and fewer emissions. It made 360 hp and a whopping 650 lb-ft of torque. These engines carried over for the Classic. A five-speed manual transmission was standard with the 6.0-liter V8, with a four-speed automatic optional. The 8.1-liter V8 and diesel engines came with either a six-speed manual or five-speed automatic (which became a six-speed for 2006).

As with the current GMC Sierra 2500HD, we were always impressed by this generation's powerful engine lineup and substantial towing and hauling abilities. It was a reasonably comfortable truck for everyday use, but don't expect the plush ride of its light-duty siblings. Any of the three available engines will provide swift acceleration and ample towing power, but the diesel V8 is probably the best choice for those who tow heavy loads -- especially the more powerful 2006 Duramax. Our principal beef concerns the shoddy interior design, materials and build quality. GMC improved it gradually during its lifespan, but it was never quite up to snuff.

The previous-generation GMC Sierra 2500 ran from 1988-'98 with a significant refresh for 1995. It was known as the Sierra 2500 Classic for 1999 and 2000. Strengths of these pickup trucks include strong, durable powertrains, while weaknesses center on sketchy build quality and materials within the cabin.

User Reviews:

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  Diesel is wonderful - 2004 GMC Sierra 2500HD
  By E. Daniel Shoemaker - October 31 - 10:00 am

  Traded in my 96 GMC 3/4 ton Suburban, w/ 454 Vortec engine for this new crew cab, Duramax w/ Allison transmission. Wow what a difference in towing power. Previously driving over mountins into Prescott and Payson, from the Phoenix area, we were lucky to keep up 35mph. Now, wow, 65mph over the same roads and mountains, towing the same trailer. Diesel milage is better than the gas by about 5 to 6 mpg. Wish the Suburban had this engine/trans.

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  GMC Sierra 2500HD 4WD 6.6L - 2008 GMC Sierra 2500HD
  By James Nichols - October 4 - 5:43 pm

  First off, after researching diesel trucks for over a year, it was clear that the Duramax/Allison power train was the "gold standard". I recently installed a Banks air intake, programmer, and exhaust system ($2500) and the performance is startling. Stock, average fuel economy was 16.2 (70 mph+ freeway); I hope the Banks package increases that up to 2 mpg. I stopped to watch a local, weeknight rodeo event in Paso Robles, CA and there were eventually 40+ trucks with 20-30 trailers, all diesels: 1 Chev, 3 Fords, the rest GMCs.

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  GMC 2500HD 4 years later - 2004 GMC Sierra 2500HD
  By Steve Coleman - September 15 - 1:53 pm

  Truck has been overall a good unit. Windsheild leak when new at passenger floorboard and behind dash. Took 1 year for local dealer to finally fix. Climate Control slow to activate fan, really noticable on hot days, seems I have to press brake pedal to start blower (wierd). Trans will sometimes start in 2nd gear, then shift to 1st. Usual problems with intermiediate steering shaft (now on 2nd fix), drivers seat belt and armrest broke, pass side also (wrty fixes). Also having wierd problem during cold months with intermittent dash light and guages recycling, no fix yet. Orig brakes are still strong at 90k miles, tire wear good, body still tight and quiet, engine strong with no oil usage

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  One Great Truck - 2008 GMC Sierra 2500HD
  By Big Rob - August 28 - 1:20 pm

  I purchased my 08 in October and now have 5000 miles on it. The fuel economy is around 16 in city and 18 on highway, but I am still in break-in period and expect improvement. Economy drops quickly north of 70 MPH. The Duramax and Allison are a great powerteam and while you can hear it shift, you cannot feel it. Interior on the SLT very well laid our and looks like it should be in a luxury car. The GM 100k warranty is a big plus. My only concern is the 26 gallon fuel tank is too small for hauling heavy trailers.

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  The time tested truth - 2005 GMC Sierra 2500HD
  By dplind - August 23 - 10:00 am

  Ok lets start out that I have owned them all and I have owned a lot of trucks. My business is repairing trucks of all sizes and brands for large and small owners. I drive what I dont have to fix! Period! The GMC gives me power to pull my toy hauler and comfort on the long vacations. looks great and never lets me down

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  Work Truck Z82 Priceless - 2007 GMC Sierra 2500HD
  By rendog - July 28 - 5:23 am

  Best truck for the buck. 98% of this truck life has been pulling a 3.5ton trailer on the hills of western PA. Its like an old hound dog ready to work. Its powerful and comfortable for the wife and kids. Handles like a long Camaro. I get about 18.8mpg @ 72mph and about 13 combined when towing. Rented a diesel but it has too much torque for stop & go. Get props every time I stop for its true work look. Only 2 problems, TPMS and an exhaust gasket failed.

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  2005 GMC 2500HD SLE Crew Cab SB 4WD 6.6L - 2005 GMC Sierra 2500HD
  By Larry Sinclair - July 11 - 7:30 am

  This 6.6L turbo with the 5 speed auto trans performs excellently whether driving empty or pulling a 30 RV. Interior is very plush (all the bells and whistles)and extremely quiet and comfortable on the road. The dash layout and field of vision behind the wheel is excellent. Added a bedrug and Pace Arrow bed-locker with power tail gate for security and improved MPG. Added ONKI brush guard for added protection from Colorado wildlife. This is a real truck for all occassions with added luxury and comfort!!! For 06 the manufacture has added 30 hp and 6 speed auto trans to an already outstanding rig.

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  Great overall family truck - 2002 GMC Sierra 2500HD
  By Mark Danley - July 6 - 2:00 am

  This has been an exceptional truck, plenty of power and quiet for a diesel. much quieter than either the Dodge or Ford. A very comfortable truck to drive. We pull a 10,000 lb 5th wheel and it pulls with little effort.

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  GM Quality - 2015 GMC Sierra 2500HD
  By Brad - July 5 - 7:50 pm

  only 1700 miles on the truck and had it in the dealer twice for an oil leak. The oil pan has surface cracking, apparently acceptable to GM as it is on every truck. The wax coating on the frame can be easily removed by a fingernail and already has rust coming through mainly on the joints as if it was not applied properly or the coating method is simply insufficient. I actually bought 2 of these trucks and both have had paint issues. the 1st truck had the 3.73 axle, which has a poor tow rating of only 9200 pounds or so. this information cannot be found on the website and the website shows you cant even get the 3.73 with the gas engine. sunglasses holder is oddly shaped and wont fit regular sunglasses. the manual shift mode doesnt allow you to shift up when coasting downhill or something. the truck always seams to be down one gear lower than it should be when coasting and tow mode is off. the passenger tow mirror is very poor for visibility and doesnt show the side of my trailer as my f150 did. the led lighting is cool but there are wires that can get snagged under the bed rails. ride is more firm than previous models which I like. Ipod playback is horrible. very slow to respond and often doesnt work at all. dealer said it works fine. air conditioner lowers for phone calls which is cool. towing uphill isnt very good. the truck bounces between 2 gears, one which is excessively high and the other is to low to maintain speed.

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  GMC HD - 2001 GMC Sierra 2500HD
  By Harris - June 20 - 4:10 am

  Best vehicle I have ever owned. Still smooth and powerful after 150,000 absolutly trouble free miles. Ford and Dodge probably have as good an engine, but no way can they match the Allison/Duramax as a package. I used to trade trucks every year, but I still enjoy this one so much I want to see just how long it will go.