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2011 GMC Sierra Denali HD 4x4

Princely Beast

GMC’s brawny HD lineup gets a big dose of luxury with the new Denali crew cab.

The previous generation of GMC’s Denali pickup line was good. The last one we tested was in 2005, and overall, we liked it as a daily driver and as a tow vehicle. However, there were a few aspects of the previous model that were open to improvement.

One, the ’05 model was available only with all-wheel drive, a powertrain we felt was unnecessary in the southern half of the United States. Two, it was available with a powerful 6.0-liter V8, but no diesel. And three, if you wanted an HD model, you could not get one in Denali trim. For 2011, all that has changed.

“The all-new 2011 Sierra Denali HD blends capability with premium features and styling,” said GMC product marketing director Lisa Hutchinson in a news release. “With its powerful, best-in-class diesel engine, the new Sierra HD models have increased towing and hauling capabilities, a key consideration for people who use them for work or for recreation, such as towing a large boat or trailer.” 

Towing With It

Towing capacity for the Denali HD, with a conventional hitch is 13,000 pounds. With a gooseneck or fifth wheel, it spikes to 16,800. We pulled a 20-foot enclosed car trailer loaded with a Mazda Miata and some spare wheels and tools. All totaled, the load weighed 5,760 pounds.

Our local test route includes some rutted stretches of freeway and a winding, 2-mile-long 7 percent grade, which provides a good test of engine torque on the way up and braking and control on the way down. First, let’s cover the ascent.

On flat terrain, with the cruise control engaged, the Denali loafed along at 60 mph 1,600 rpm in fifth gear. According to the onboard computer, it was netting 14 mpg, too. What is telling is that as we ascended the grade, the truck never downshifted or slowed at all. It maintained 60 mph in fifth gear. That is what 765 pound-feet of torque will do for you. Mileage figures on the dash display immediately began dropping to a low point of 12.5 mpg, however.

On a downhill grade, the Denali HD solidified its place as one of the most competent tow vehicles we’ve tested. Here’s why. With the cruise control engaged at 55 mph and the exhaust brake enabled, the truck maintained that speed all the way down the grade—and yet we never touched the brakes. The intelligent system worked exactly as West Coast GM spokesman Richard James said it would.

“This driver-selectable feature uses the turbine control of the variable geometry turbocharger and the compression of the engine to generate backpressure, slowing the vehicle without applying the brakes,” James said in an email. “It is integrated with the cruise control feature, and varies the braking to account for the grade and vehicle load. The exhaust brake allows for virtually effortless driving and towing, with seamless and quiet operation. It also helps prolong brake life and prevents overheating the brakes on long, downhill grades.”

The transmission also did its part, holding fourth gear until we were back on flat terrain. It even rev-matches the engine on downshifts as you decelerate for a turn.

A few other towing-friendly features worth noting are the “passing” turn signals, which automatically flash three times without a trailer and five times when a trailer harness is connected. In addition, the rearview camera system displayed on our test vehicle’s navigation system display. You can get a backup camera without a nav system, but the video feed displays on the rearview mirror. We also appreciated the right-hand rearview mirror, which automatically lowered its orientation when the truck is shifted into reverse. It is interesting to note that the Denali uses the standard mirrors, which were perfectly suitable for seeing past an 8-foot-wide trailer, and they made it easier to drive the truck on tight streets between parked and oncoming cars.

Living With It

A telling sign of a vehicle’s good looks is whether you turn back to catch a glimpse of it as you walk away. We found ourselves doing that a lot, and from different angles. The onyx black paint was punctuated by tasteful chrome accents and other “jewelry” on the exterior. We rarely comment on style, because it’s largely a personal issue, but this is a good-looking truck.

Inside, the ebony front seats were heated and cooled, a key benefit of the perforated leather seating surfaces, one of several excellent choices in materials used throughout the interior. The interior exhibited fine fit and finish, with even gaps and seams, and it used harder, more durable plastics in high-wear areas. The interior is not on par with, say, that of an Audi, in terms of design, materials and quality, but for a pickup truck—any pickup truck—the inside of the Denali was first rate.

We also liked the wheel-mounted stereo and cruise-control switches. Easy to learn and operate, they minimized the need to look away from the road. In terms of handy features, the rear seats lifted with one hand, which is great if your other hand is holding a bag of groceries or a small child. Likewise, the easy-lift tailgate was light enough to raise and lower with one hand.

Around town, mileage was on par with gasoline-powered trucks, around 12.5 mpg, but our test vehicle had traveled less than a thousand miles, so as the engine breaks in, mileage should improve.

A couple of aspects that will not improve—owners will just have to get used to them—are the sheer size of the vehicle and its rather large turning circle. We measured the radius at five lanes, which is right in line with GM’s figure of 50.5 feet. Also, the truck’s size is such that it will have you skipping open parking spaces—because it just will not fit—in favor of other spaces with no cars in the  adjacent slots. You know, farther out in the parking lot. However, because of the smaller conventional mirrors, it is less of an issue than it was with the towing-mirror-equipped Silverado we also tested.


The 2011 GMC Denali HD is a princely beast, a luxurious heavy-duty pickup ideal for towing a large trailer or a big boat. If you intend to use it as a daily driver, however, and your trailer is, say, 9,000 pounds or less, you likely would be better served with the half-ton version of the Denali.


Ford F-250 Super Duty, Dodge Ram HD 2500

- Luxurious interior trim

- Awesome Duramax/Allison powertrain is quiet and powerful

- Not much bigger than half-ton crew cab

- Solid cabin feel
- Fifth and sixth gears overdriven

- Exhaust braking system effective and intelligent
- Factory brake controller
- Excellent brake feel and power

- Could use a telescoping steering column 

- $60 to refill diesel exhaust fluid every 5,000 miles
- Lacks express down and up window function on all four windows
- Huge turning circle

EPA Fuel Economy Estimates

City NA
Highway NA


0-60 mph towing 17.35 seconds

40-60 mph towing 7 seconds
0-60 mph nontowing 8.9 seconds

40-60 mph nontowing 4.8 seconds


Engine 6.6 liter Duramax V8 turbodiesel
Horsepower 397 @ 3,000 rpm

Torque 765 lb./ft @ 1,600 rpm

Compression ratio 16:1
Transmission Six-speed Allison auto., with tow/haul and manual modes


Curb weight 7,391 lbs.

Tow rating 13,000 lbs. w/conventional hitch/16,800 w/fifth wheel, gooseneck
Gross vehicle weight rating 10,000 pounds


Axle ratio 3.73:1
Fuel capacity 36 gal.
Tire size 
 LT265-60R20 Goodyear Wrangler SR-A
Brakes Four-wheel hydroboost disc, w/antilock
Suspension Front: Short/long arm torsion bar
Rear: Live axle with five-leaf springs, opposed shocks


Overall length 20’
Maximum width 80”
Wheelbase 153.7”
Base price $46,450
Price as tested $61,774


20’ enclosed trailer loaded with 1995 Mazda Miata

5,760 lbs.


Customer service 800-462-8782
Web site



With 765 pound-feet of torque available at just 1,600 rpm, the Sierra Denali HD was barely fazed by the 5,760-pound trailer, which connected to the 2.5-inch receiver, and came with an adapter to accommodate 2.25-inch draw bars.

Despite the all-business powertrain and towing equipment, the Sierra Denali HD came decked out with a luxurious interior, with heated and cooled leather seats, a heated steering wheel and a built-in trailer brake controller.

Rear seats lift with just one hand, great for those times when a child or grocery bag is in the other. Handsome from every angle, the Sierra Denali has an easy-lift tailgate, which is still made of steel, but is much lighter than that of the previous generation.

Our test model came equipped with satellite navigation. The rearview camera system displays the feed on the in-dash screen when the gear lever is notched into reverse. Denali trim includes some tasteful "jewelry" inside and out.



2011 GMC Denali HD, towing with a Denali, Sierra Denali HD


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