2021 GMC Sierra 1500 AT4 vs. 2021 Chevrolet Silverado 1500 LT Trail Boss

Sierra AT4 vs. Silverado LT Trail Boss comparison banner

When you need an off-road pickup, you can put your trust in either GMC or Chevrolet to provide you with the truck to accomplish all of your tough terrain tackling needs. The AT4 and LT Traiboss trims of the Sierra 1500 and Silverado 1500, respectively, are the models in the lineup most primed for adventure, easily transitioning from work to play. While similar in a lot of aspects, there are many differences that separate the Sierra AT4 from the Chevrolet LT Trail Boss, from engine options to colour availability to available tech and more. Explore with us at Ernie Dean as we break down some of the main highlighted differences between these two pickups, and outline which one may be the best fit for you!


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Exterior Design


Dimensions: 2021 GMC Sierra 1500 AT4 Crew Cab 2021 Chevrolet Silverado 1500 LT Trail Boss Crew Cab
Length (mm/in) 6,128 / 241.3 6,127 / 241.2
Width (mm/in) 2,063 / 81.2 2,063 / 81.2
Height (mm/in) 1,987 / 78.2 1,987 / 78.2
Wheelbase (mm/in) 3,989 / 157.1 3,989 / 157.1
Cargo Box Length (on floor) (mm/in) 2,018 / 79.4 2,018 / 79.4
Cargo Box Width (on floor) (mm/in) 1,814 / 71.4 1,814 / 71.4
Ground Clearance 272 / 10.7 272 / 10.7


Like the Sierra and Silverado models at large, both of these pickups provide almost exactly similar specifications, but it’s in their actual looks that differentiate the two. The AT4 has more aggressive styling, however the LT Trail Boss is sharp on its own with its gloss black wheels. There are many fine detail differences between the two, including these main highlights below:



  • AT4:
    • 18 inch tires (Goodyear Wrangler DuraTrac tire, or all-season tire)
    • 20 inch tires (Goodyear Wrangler Territory tire, or all-season tire)
    • Paint-matched grille surround (black grille), mirror caps, door handles, rear bumper, red tow hooks
    • New running board with box liner grip, higher ground clearance than Trail Boss
    • Backdoor keyless entry
    • MultiPro tailgate
    • Carbon fibre box option


  • LT Trail Boss
    • 18 inch tires (no all-season option)
    • 20 inch tires (no all-season option)
    • Gloss black wheels
    • Black grille, bumper, mirror caps, door handles, rear bumper, red tow hooks
    • No backdoor keyless entry
    • Standard tailgate (MultiFlex tailgate soon available)


Side interior view of Chevrolet LT Trailboss

Interior Design


Dimensions: 2021 GMC Sierra 1500 AT4 Crew Cab 2021 Chevrolet Silverado 1500 LT Trail Boss Crew Cab
Front Headroom (mm/in) 1,093 / 43.0 1,093 / 43.0
Rear Headroom (mm/in) 1,019 / 40.1 1,019 / 40.1
Front Legroom (mm/in) 1,131 / 44.5 1,131 / 44.5
Rear Legroom (mm/in) 1,102 / 43.4 1,102 / 43.4
Front Shoulder Room (mm/in) 1,677 / 66.0 1,677 / 66.0
Rear Shoulder Room (mm/in) 1,655 / 65.2 1,655 / 65.2
Front Hip Room (mm/in) 1,554 / 61.2 1,554 / 61.2
Rear Hip Room (mm/in) 1,530 / 60.2 1,530 / 60.2
Passenger Capacity 5 5


Just like the exterior, the interior of these trucks maintains the same dimensions, getting you the same amount of room in each. From there it comes down to the features available, with the more luxurious AT4 model offering up more for your liking, including a rear camera, Head-up Display, rear heated seats and more. The LT Trail Boss, though, does offer more interior colour and seat options. Explore their prime differences below:



  • AT4:
    • Leather seat material (no cloth option)
    • Jet Black (with Kalahari accents) interior colour (only option)
    • Memory seat options, with front passenger power adjustment
    • Rear heated seats
    • Standard wireless charging
    • Standard wireless Apple CarPlay and Android Auto
    • Rear camera mirror (available)
    • Head-up Display (available)


  • LT Trail Boss: 
    • Leather or cloth seat material
    • Jet Black or Gideon/Very Dark Atmosphere interior colour options
    • Front passenger seat adjustment is manual (no power)
    • Standard wired Apple CarPlay and Android Auto (wireless available)
    • No wireless charging
    • No Rear camera mirror
    • No Head-up Display





Engines: 5.3L EcoTec3 V8 3.0L Duramax Turbo-Diesel I6 6.2L EcoTec3 V8
Transmission 8-speed or 10-speed automatic 10-speed automatic 10-speed automatic
Horsepower 355 277 420
Torque (lb-ft) 383 460 460
Available On AT4 & LT Trail Boss AT4 AT4 & Trail Boss


As both of these trims are their respective model’s off-road editions, they each come with an off-road package, the Z71 for the LT Trail Boss and the X31 for the AT4. While these packages have two different names, they provide the exact same features, including a 2-inch factory suspension lift, underbody skid plate, heavy duty air filter, 2-speed transfer case, Hill Descent Control and dual exhaust. Both the 5.3L and 6.2L engines are available on either model, while the AT4 is the only one between the two available with the fuel-efficient 3.0L diesel engine option.



Verdict: Which Pickup is For You?


Engine Pricing: 2021 GMC Sierra 1500 AT4 2021 Chevrolet Silverado 1500 LT Trail Boss
5.3L EcoTec3 V8 $63,848* $58,748*
3.0L Duramax Turbo-Diesel I6 $65,843* N/A
6.2L EcoTec3 V8 $66,693* $61,593*


The 2021 GMC Sierra 1500 AT4 Crew Cab Short Bed starts at $63,848 and the 2021 Chevrolet Silverado 1500 LT Trail Boss starts at $58,748. That’s around a 5K price difference right off the bat, due to the many more features and luxurious availability on the Sierra. There’s more options to be had on the AT4, thus its price gets a lot higher than the LT Trail Boss’s as you add on packages to either. Both pickups offer many similar features and have equal off-road intentions, but with the AT4 providing a bit more elegant and feature-heavy options. If you want the best of the best and a loaded pickup with the latest features and tech, the AT4 is for you, but if you’re content with the base ability and capability the LT Trail Boss has to easily satisfy your off-road needs, it’s a solid choice as well.


Ernie Dean is Truckville, meaning we’re your go-to destination in Alliston and Ontario at-large to not only find yourself a new or used pickup, but also just to learn even more about these legendary GM trucks. Contact us, today, whether you just have a few questions, need service, or have your eye on driving home in an unbeatable GMC or Chevrolet truck.