2006 GMC Sierra 2500HD Review | Edmunds.com

2006 GMC Sierra 2500HD

Certified Pre-Owned (CPO) is a category of used car. Often late-model vehicles, they have been inspected, refurbished, if necessary, and are under warranty by the manufacturer.
GMC Sierra 2500HD Features and Specs

Features & Specs

  • Engine 6.0 L V 8-cylinder
  • Drivetrain Rear Wheel Drive
  • Transmission 4-speed Automatic
  • Horse Power 300 hp @ 4400 rpm
  • Fuel Economy 0/0 mpg
  • Bluetooth No
  • Navigation No
  • Heated Seats No

Review of the 2006 GMC Sierra 2500HD

  • With its numerous powertrain and cab configurations, and stout towing and hauling capacities, the Sierra HD is a hard truck to beat for those who need maximum functionality and capability.

  • Safety
  • Pros

    Powerful engine lineup, multiple drivetrain configurations, substantial towing and hauling capacities.

  • Cons

    Spotty build quality, mediocre design and interior materials.

  • What's New for 2006

    For 2006, the Duramax diesel engine receives a host of power and refinement upgrades, as well as reduced emissions. The Allison automatic transmission is now a six-speed, and features a tap-shift range selection mode. The camper-style mirrors have been replaced by a folding and extending design with a built-in convex spotter glass. Trim levels and packaging have also been juggled.

What Others Are Saying

Customer Reviews

1 of 1 people found this review helpful

Opinion on recent used purchase

by on
Vehicle: 2005 GMC Sierra 2500HD

Just bought this truck from my neighbor. 58,000 miles on a 8 year old truck. It is box stock and clean. I cleaned it up even more. I have never owned a diesel before or a GMC. This diesel is Awesome! GMC has a slightly better finish than the Silverado I sold. We tow a 33ft Keystone Ultra lite camper that's 6,800lbs like a dream. There all expensive and I don't know why the comman man would spend the money on a new one. Enjoy shopping and go clean used. Some mods in the future, good deals out there on used perf. parts

1 of 1 people found this review helpful

The time tested truth

by on
Vehicle: 2005 GMC Sierra 2500HD

Ok let's 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 don't 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

1 of 1 people found this review helpful

Great truck

by on
Vehicle: 2005 GMC Sierra 2500HD

I purchased this truck in April 2010. My first gmc. I love it. It has the duramax & Allison combo. Very powerful. It pulls beyond what I expected. I got this truck used with 81 thousand miles. Everyone tells me its just getting broke in. So far I like everything about this truck.

Hi oh silver

by on
Vehicle: 2005 GMC Sierra 2500HD

i love my pickup, hauls my 40HP massey with bucket and brush hog like it's not even there. with banks big hoss bundle it hauls balls and doesn't think twice. awesome truck wouldn't give anything for it. it's dependable, and with all the mods it catches eyes everywhere i go. as of now, until ford puts out the 6.7L would only recommend a duramax. cummins is good but everything around it is crap and rides like a semi. duramax is king right now. i just can't say how much i love my pickup.

Speedometer problems

by on
Vehicle: 2005 GMC Sierra 2500HD

I bought my Duramax Diesel 2500 Hd crew cab to pull a 36 foot fifth wheel. There is plenty of power; however, have had a few problems. The speedometer failed at about 60000 miles and had to be replaced. I have read that this is a common problem but there is a class action lawsuit and I plan to turn in my 478.00 receipt and hopefully get reimbutsed from GM. The engine light came on and paid to have the code read which was relatively meaningless but haven't had any more problems with that. I added a Superchip which is amazing how much perfromance improvement. Have heard that some people have burned up transmission with Superchip but I always reset to towsafe prior to pulling anything.

1 of 1 people found this review helpful

05' 6.6 v8

by on
Vehicle: 2005 GMC Sierra 2500HD

Very nice truck. Lots of power for pulling my 35 foot race trailer. Good on fuel about 21 highway 18 in town. I put the banks 6 gun chip in it. Very fast. Sounds good and has lots of power

Full 2006 GMC Sierra 2500HD Review

What's New for 2006

For 2006, the Duramax diesel engine receives a host of power and refinement upgrades, as well as reduced emissions. The Allison automatic transmission is now a six-speed, and features a tap-shift range selection mode. The camper-style mirrors have been replaced by a folding and extending design with a built-in convex spotter glass. Trim levels and packaging have also been juggled.


GMC's modern full-size pickup has been around in one form or another since the early '60s. Now into its sixth generation, the Sierra, as it's now called, boasts classic styling and a wide variety of body styles and drivetrains. A perennial competitor to the full-size offerings from Ford and Dodge, GMC positions itself as the professional grade truck in GM's lineup. Although its sales numbers are far below those of its competitors, when combined with its sister vehicle, the Chevrolet Silverado, the GM trucks sell in competitive numbers to Ford's F-Series.

Often first to market with exclusive features, the Sierra 2500HD continues that tradition by offering XM Satellite Radio and Bose audio systems. GMC trucks also offer the OnStar communications system that provides the convenience of 24-hour on-call assistance for everything from tow truck requests to dinner reservations. Combine this with attractive styling on the outside and thoughtful features on the inside, and the Sierra 2500HD presents a compelling package for anyone in the market for a no-holds-barred work truck. Solid as the heavy-duty Sierra is, it's definitely worth your while to shop around in this segment, as Ford and Dodge both have strong diesel power plants that give their trucks higher tow ratings. GM's truck is still a fine choice for use around the worksite and home, especially if you decide you don't need the grunt of diesel -- just make sure you assess your needs carefully before making a decision.

Body Styles, Trim Levels, and Options

The 2500HD is available in regular, extended and crew cab body styles in both two- and four-wheel drive. Short or long boxes are available except on regular cabs, which are long boxes only. There are several levels: Work Truck, SL1, SLE1, SLE2 and SLT. True to their name, Work Trucks offer only the basics, but you still get manual dual-zone air conditioning, a 40/20/40-split bench seat and ABS. SL1 models come standard with a tilt steering wheel, cruise control, an AM/FM/CD stereo, driver message center and tinted glass. SLE1 models add power windows and door locks, remote keyless entry, power-heated exterior mirrors, foglamps and a leather-wrapped steering wheel. SLE2 models provide a six-way power driver seat and an upgraded Bose stereo. Top-of-the-line SLTs add leather bucket seats with heaters, driver-seat memory and dual 10-way power adjustments, automatic climate control, power-retractable mirrors and satellite steering wheel controls.

Powertrains and Performance

The HD's base engine is a 6.0-liter V8 rated at 300 horsepower and 360 pound-feet of torque. GMC offers two even more powerful options: an 8.1-liter V8 and the 6.6-liter Duramax turbodiesel. The 8.1-liter engine boasts an impressive 330 hp and 450 lb-ft of torque, while the Duramax diesel makes as much as 360 hp and 650 lb-ft of torque. The standard transmission for the 6.0-liter V8 is a five-speed manual with a four-speed automatic optional. The 8.1-liter V8 and Duramax diesel can be hooked up to either a six-speed manual or a heavy-duty Allison six-speed automatic. Being heavy-duty trucks, these brutes can certainly pull -- the maximum towing capacity of the 2500HD with the 6.0-liter engine is 10,500 pounds, while the 8.1-liter V8 can tow up to 12,000 pounds.


Four-wheel antilock disc brakes are standard. In frontal crash tests conducted by the National Highway Traffic Safety Administration, a Sierra earned a three-star rating (out of five) for driver protection and four stars for the front passenger. In the Insurance Institute for Highway Safety's frontal offset crash test, the Sierra was given an overall rating of "Marginal," the second lowest.

Interior Design and Special Features

Inside, Sierra buyers will find a logically laid-out interior with an easy-to-use dual-zone climate control system and clear, uncluttered gauges. Materials quality is unimpressive, and build quality, though improved over the last few years, is still behind the competition. The large cabin offers plenty of room and comfortable bucket seats.

Driving Impressions

The 2500HD is a reasonably comfortable truck for everyday use, but don't expect the plush ride of its light-duty siblings. Any of the available engines provide swift acceleration and ample towing power, but the Duramax diesel is probably the best choice for those who tow heavy loads. The manual transmissions are about what you would expect in a big truck, but the automatics shift smoothly and crisply no matter how heavy the load.

Talk About The 2006 Sierra 2500HD

Gas Mileage


  • Not Available
  • cty
  • Not Available
  • highway
Calculate Yearly Fuel Costs
Have a question? We're here to help!
Chat online with us
Email us at help@edmunds.com
*Available daily 8AM-5PM Pacific