top of page
Writer's pictureMike Hagerty

Size Matters: The 2021 GMC Sierra 2500 Denali 4WD Crew Cab


2021 GMC Sierra 2500 Denali 4WD Crew Cab front 3/4 view

In an era when even half-ton two-wheel-drive pickups are big, 3/4-ton four-wheel-drives are HUGE. Behold the 2021 GMC Sierra 2500 Denali 4WD Crew Cab. It stands six feet, nine-point-eight-two inches tall. It's very nearly seven feet wide, without its mirrors.


2021 GMC Sierra 2500 Denali 4WD Crew Cab rear 3/4 view

Length? Beats me. It's not listed on GMC's specs. The wheelbase is, and it's 158.94 inches. A Kia Rio 5-door ----an entire Kia Rio 5-door---the whole car---is only 1.06 inches longer than the space between the front and rear wheels of this truck.


There's a debate going on in certain circles over whether these are magnificent beasts or threats to the public at large. Not gonna go there, other than to say that the "right tool for a certain job" philosophy is one I ascribe to. If I'm driving to and from work, I probably want a midsize sports or luxury sedan. If I'm going for a drive on a winding back road, a nice, nimble two-seater is just the ticket. Transporting four people in comfort? An SUV. Six people? A minivan.


If it's a run to Home Depot or the garden store, or towing something small to middle-sized, a half-ton pickup is a great choice.


And if I'm going to carry a heavier load in the bed of the truck, or tow a trailer or a boat heavier than a half-ton pickup can safely handle, this is exactly what I want to be driving. But damn, it's big.


2021 GMC Sierra 2500 Denali 4WD Crew Cab hood up

2021 GMC Sierra 2500 Denali 4WD Crew Cab hood up closer

Here's what I'm talking about. I stand six feet even. The above picture was taken standing at the edge of the front bumper with my camera at eye level. Looks like there might be an engine in there.


2021 GMC Sierra 2500 Denali 4WD Crew Cab engine

If I raise my hands above my head and tilt the camera down---now I can see the engine. It, by the way, is a 6.6-liter Duramax turbodiesel. 445 horsepower. NINE HUNDRED AND TEN pounds per foot of torque at a mere 1600 rpm. This is why the 2021 GMC Sierra Denali 4WD Crew Cab has a max conventional trailering rating of 18,500 pounds. The right tool for the job.


It's mated to a ten-speed Allison automatic transmission. That engine, by the way, is a $9.750 option, replacing the standard 401 horsepower, 464 pounds per foot of torque gasoline V8 engine mated to a six-speed automatic, which gives up 4,000 pounds of max conventional trailering for a still-strong 14,500. EPA fuel economy ratings are, as the window sticker says, "not directly comparable" to light-duty trucks. In 100 miles of city streets, urban freeways and Sierra Nevada backroads, I averaged 14.5 miles per gallon. Not bad.


Mike reaches for the hood of the 2021 GMC Sierra 2500 Denali 4WD

Let's go back to size for a moment. I've been saying for the past few years that the styling trend of bigger, bluffer, allegedly more "macho" front ends for trucks was past the point of self-parody. At six feet tall, with a 35-inch sleeve, I can only barely reach the hood of modern half-tons to close them.


With the 2021 GMC Sierra 2500 Denali 4WD Crew Cab, I have finally met the hood too tall for me to reach. Closing it meant (and would mean for pretty much anyone under 6'2") going around to the side of the truck to where the hood and the windshield meet and pushing it down from there. This is not a byproduct of form meeting function. This is styling departments trying to out-badass each other and it has gone too far. RAM appears to be the only truckmaker that understands power can be expressed horizontally as well as vertically.


2021 GMC Sierra 2500 Denali Crew Cab 4WD flexible tailgate

2021 GMC Sierra 2500 Denali Crew Cab 4WD flexible tailgate

2021 GMC Sierra 2500 Denali Crew Cab 4WD tailgate down

2021 GMC Sierra 2500 Denali Crew Cab 4WD tailgate down-side

GMC's MultiPro tailgate is standard. The above photos are only two of the ways you can open it. Here's a rundown on the various ways it can be used.


2021 GMC Sierra 2500 Denali Crew Cab 4WD bed

2021 GMC Sierra 2500 Denali Crew Cab 4WD power outlet

2021 GMC Sierra 2500 Denali Crew Cab 4WD trailering outlet

Also standard, a spray-in bedliner, drain plugs, a sliding rear window LED bed lighting and easily accessible power outlets for trailering and other uses.


2021 GMC Sierra 2500 Denali Crew Cab 4WD rear seat

2021 GMC Sierra 2500 Denali Crew Cab 4WD front seats

2021 GMC Sierra 2500 Denali Crew Cab 4WD front seat detail

2021 GMC Sierra 2500 Denali Crew Cab 4WD instrument panel

The base price of the 2021 GMC Sierra 2500 Denali 4WD Crew Cab is $64,900. The window sticker is at the end of the review so you can see for yourself, but among the standard equipment not already mentioned at that price is front and rear park assist, lane change alert with side blind zone alert, rear cross-traffic alert, forward collision alert, lane departure warning, automatic emergency braking and following distance indicator----but not adaptive cruise control. This essential safety feature increasingly standard on $20,000 cars is either part of an extra-cost tech package or simply unavailable on certain GM models. Also on the standard list, HD Surround Vision with provision for two trailer cameras, an auto-locking rear differerential, a two-speed automatic transfer case, an X31 off-road suspension with Rancho shocks, Stabilitrak and trailer sway control , all-terrain tires, a trailering system, an Bose premium audio system with navigation, and heated and ventilated 10-way power front seats.

2021 GMC Sierra 2500 Denali Crew Cab 4WD steering wheel and gauge cluster


2021 GMC Sierra 2500 Denali Crew Cab 4WD gauge cluster

2021 GMC Sierra 2500 Denali Crew Cab 4WD center stack

Our tester did have some extra-cost options, besides the 6.6-liter diesel mentioned above: $2,270 for the Denali Ultimate Package (see window sticker below for details), $545 for a gooseneck/5th wheel prep package, and $195 for the Onyx Black paint job. So with $1,595 destination charge, the as-tested price of the 2021 GMC Sierra 2500 Denali 4WD Crew Cab would be $79,255---but there's a $500 Denali Ultimate Package discount, so the real bottom line is $78,755.


2021 GMC Sierra 2500 Denali Crew Cab 4WD front view

2021 GMC Sierra 2500 Denali Crew Cab 4WD side view

2021 GMC Sierra 2500 Denali Crew Cab 4WD rear view

Not owning a boat, a horse trailer, a fifth-wheel or any of the other things that might require the prodigious hauling capacity of the 2021 GMC Sierra 2500 Denali 4WD Crew Cab, it's not for me. But I absolutely can appreciate it as a high-quality tool for the job.


Click on the image to go to the Sierra HD page on the GMC website.

MHC Banner.png
  • Facebook
  • Instagram
  • X
bottom of page