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Fullsize Crew Cab

Truck

AWD4WD

8-Cylinder

Flexible Fuel

Used

Sierra 3500

SLE Preferred Package

Suspension Package, Off-Road

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Used 2013 GMC Sierra 3500 SLE w/ SLE Preferred Package

Used 2013 GMC Sierra 3500 SLE w/ SLE Preferred Package Thornton CO 80234

Automatic

Gasoline

Sierra Convenience Package

Used 2015 GMC Sierra 3500 2WD Regular Cab w/ Sierra Convenience Package

Used 2015 GMC Sierra 3500 2WD Regular Cab w/ Sierra Convenience Package Fort Lupton CO 80621

2WD Regular Cab

8-Cylinder Turbo

Diesel

Used 2011 GMC Sierra 3500 Denali

Used 2011 GMC Sierra 3500 Denali Longmont CO 80504

Denali

Remote Start Package

Used 2023 GMC Sierra 3500 SLE w/ Remote Start Package

Used 2023 GMC Sierra 3500 SLE w/ Remote Start Package Henderson CO 80640

Fullsize

Sport Utility

6-Cylinder

Acadia

Driver Convenience Package

Used 2020 GMC Acadia SLE w/ Driver Convenience Package

Used 2020 GMC Acadia SLE w/ Driver Convenience Package Denver CO 80234

Gooseneck/5TH Wheel Prep Package

Heavy Duty Front Spring/Camper Package

Used 2024 GMC Sierra 3500 Denali Ultimate

Used 2024 GMC Sierra 3500 Denali Ultimate Englewood CO 80113

Denali Ultimate

Sierra 2500

Used 2022 GMC Sierra 2500 SLE

Used 2022 GMC Sierra 2500 SLE Denver CO 80234

Denali Reserve Package

LPO, Hitch Package

New 2025 GMC Sierra 3500 Denali w/ Denali Reserve Package

New 2025 GMC Sierra 3500 Denali w/ Denali Reserve Package Castle Rock CO 80104

SLT Premium Package

X31 Off-Road and Protection Package

Gooseneck/5TH Wheel Package

Used 2021 GMC Sierra 3500 SLT w/ SLT Premium Package

Used 2021 GMC Sierra 3500 SLT w/ SLT Premium Package Dacono CO 80514

SLE Value Package

Preferred Package

X31 Off-Road Package

New 2025 GMC Sierra 3500 SLE w/ SLE Value Package

New 2025 GMC Sierra 3500 SLE w/ SLE Value Package Loveland CO 80538

Sierra 1500

Used 2018 GMC Sierra 1500 4x4 Double Cab

Used 2018 GMC Sierra 1500 4x4 Double Cab Denver CO 80234

4x4 Double Cab

Used 2025 GMC Sierra 3500 Denali Ultimate

Used 2025 GMC Sierra 3500 Denali Ultimate Denver CO 80221

SLE Convenience Package

Used 2023 GMC Sierra 2500 SLE w/ SLE Convenience Package

Used 2023 GMC Sierra 2500 SLE w/ SLE Convenience Package Denver CO 80234

Convenience Package

Skid Plate Package, Frame-Mounted Shields

Used 2008 GMC Sierra 3500 SLT w/ Convenience Package

Used 2008 GMC Sierra 3500 SLT w/ Convenience Package Longmont CO 80501

Midsize

4-Cylinder Turbo

Terrain

License Plate Front Mounting Package

Used 2022 GMC Terrain SLT

Used 2022 GMC Terrain SLT Denver CO 80234

Used 2024 GMC Terrain SLT

Used 2024 GMC Terrain SLT Denver CO 80234

Used 2022 GMC Sierra 3500 SLT

Used 2022 GMC Sierra 3500 SLT Broomfield CO 80020

AT4 Preferred Package

Technology Package

Driver Alert Package I

Driver Alert Package II

Used 2023 GMC Sierra 3500 AT4 w/ AT4 Preferred Package

Used 2023 GMC Sierra 3500 AT4 w/ AT4 Preferred Package Fort Collins CO 80525

AT4 Premium Package

Used 2020 GMC Sierra 3500 AT4 w/ AT4 Premium Package

Used 2020 GMC Sierra 3500 AT4 w/ AT4 Premium Package Boulder CO 80301

Used 2023 GMC Sierra 1500 Denali w/ Denali Reserve Package

Used 2023 GMC Sierra 1500 Denali w/ Denali Reserve Package Denver CO 80234

Used 2020 GMC Sierra 3500 AT4 w/ AT4 Premium Package Henderson CO 80640

Compact Crew Cab

Canyon

Elevation Premium Package

Used 2024 GMC Canyon Elevation w/ Elevation Premium Package

Used 2024 GMC Canyon Elevation w/ Elevation Premium Package Denver CO 80234

Elevation

Used 2024 GMC Sierra 3500 HD Crew Cab AT4 Pickup 4D 6 1/2 ft

AT4 Premium Plus Package

Used 2024 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package

Used 2024 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package Parker CO 80134

Duramax Plus Package

Used 2019 GMC Sierra 3500 Denali w/ Duramax Plus Package

Used 2019 GMC Sierra 3500 Denali w/ Duramax Plus Package Longmont CO 80504

Denali Ultimate Package

Gooseneck/5th Wheel Prep Package

Used 2021 GMC Sierra 2500 Denali w/ Denali Ultimate Package

Used 2021 GMC Sierra 2500 Denali w/ Denali Ultimate Package Denver CO 80234

Used 2021 GMC Sierra 3500 Denali w/ Denali Ultimate Package

Used 2021 GMC Sierra 3500 Denali w/ Denali Ultimate Package Wheat Ridge CO 80033

Used 2020 GMC Sierra 3500 Denali w/ Denali Ultimate Package

Used 2020 GMC Sierra 3500 Denali w/ Denali Ultimate Package Fort Collins CO 80525

Fullsize Extended Cab

Power Pack Plus

Used 2008 GMC Sierra 1500 SLE w/ Power Pack Plus

Used 2008 GMC Sierra 1500 SLE w/ Power Pack Plus Denver CO 80234

Used 2024 GMC Sierra 3500 SLE w/ SLE Convenience Package

Used 2024 GMC Sierra 3500 SLE w/ SLE Convenience Package Loveland CO 80537

LPO, Cargo Convenience Package

Used 2023 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package

Used 2023 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package Denver CO 80234

Used 2020 GMC Sierra 3500 AT4 w/ AT4 Premium Package Highlands Ranch CO 80126

Used 2024 GMC Sierra 3500 Denali w/ Technology Package

Used 2024 GMC Sierra 3500 Denali w/ Technology Package Highlands Ranch CO 80126

Used 2024 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package Loveland CO 80537

All-Terrain HD Package, For Crew Cab Models Only

Gooseneck/5TH Wheel Prep Package -- Hitch Platform to Accept Gooseneck or Fifth Wheel Hitch.

LPO, Hitch Package, Gooseneck Ball and Chain Tiedown Kit With Case

Used 2018 GMC Sierra 3500 SLT w/ Duramax Plus Package

Used 2018 GMC Sierra 3500 SLT w/ Duramax Plus Package Highlands Ranch CO 80126

Used 2017 GMC Sierra 3500 Denali w/ Duramax Plus Package

Used 2017 GMC Sierra 3500 Denali w/ Duramax Plus Package Highlands Ranch CO 80126

Used 2022 GMC Sierra 3500 Denali

Used 2022 GMC Sierra 3500 Denali Centennial CO 80112

Used 2017 GMC Sierra 3500 Denali w/ Duramax Plus Package Lone Tree CO 80124

Used 2020 GMC Sierra 3500 AT4 w/ AT4 Premium Package Englewood CO 80113

Advanced Safety Package

Comfort Package

Used 2019 GMC Terrain Denali w/ Advanced Safety Package

Used 2019 GMC Terrain Denali w/ Advanced Safety Package Denver CO 80234

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Cars for Sale

Shop, watch video walkarounds and compare prices on GMC Sierra 3500 listings in Longmont, CO. See Kelley Blue Book pricing to get the best deal. Search from 139 GMC Sierra 3500 cars for sale, including a Certified 2025 GMC Sierra 3500 Denali, a Used 2008 GMC Sierra 3500 SLT, and a Used 2011 GMC Sierra 3500 Denali ranging in price from $22,999 to $105,365.

GMC Sierra 3500 for Sale in Longmont, CO - Kelley Blue Book

Search from 139 GMC Sierra 3500 for sale, including a Used 2008 GMC Sierra 3500 SLT w/ Convenience Package, a Used 2011 GMC Sierra 3500 Denali, and a Used 2013 GMC Sierra 3500 SLE w/ SLE Preferred Package ranging in price from $22,999 to $105,365.

Autotrader has 139 GMC Sierra 3500 for sale near Longmont, CO, including a Used 2008 GMC Sierra 3500 SLT w/ Convenience Package, a Used 2011 GMC Sierra 3500 Denali, and a Used 2013 GMC Sierra 3500 SLE w/ SLE Preferred Package ranging in price from $22,999 to $105,365.

Frankie Rogers is a senior editor for Kelley Blue Book and focuses on the production of content. She edits and formats content, creates monthly deals lists, is a media asset curator, and photographs cars for various articles and inclusion in KBB’s image library. Her 16+ years at Kelley Blue Book have included roles as a Blue Book copy editor, press vehicle wrangler, and VIN analyst. In her spare time, she can be found tinkering with her 1970 Chevrolet Camaro, trying out new recipes in her cast iron pans, and spoiling her two cats, Grayson and Thaddeus.

Frankie Rogers

Colin Ryan, Author at Kelley Blue Book

Matt Degen is an author specializing in reviewing cars with the goal of helping you find the best one for your needs. Prior to joining Kelley Blue Book in 2012, he was a writer and editor for over a decade at The Orange County Register newspaper. There he covered automobiles, music and food -- all things Matt is passionate about. He holds degrees in Communications and Culinary Arts. When not evaluating vehicles, he is cooking on his YouTube channel.

Matt Degen

Convertible

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High End Luxury Car

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2026Mercedes-Benz Mercedes-Maybach SL

2026Mercedes-Benz Mercedes-Maybach SL Archives - Kelley Blue Book

convertible

convertible Archives - Kelley Blue Book

luxury

luxury Archives - Kelley Blue Book

$73,500 &amp; up

$73,500 &amp; up Archives - Kelley Blue Book

2-Line Blurb

140-Character Blurb

The 2026 Mercedes-Maybach SL brings ultimate plushness to the company’s much-lauded roadster.

Cons

Power, Ride, and Handling

Driving Impressions

If a Maybach SL owner is the lucky recipient of a trust fund, well here’s the thrust fund. This SL 680 enjoys a forceful 577-horsepower V8 humming away under the hood and it’s capable of accelerating from standstill to 60 mph in an estimated four seconds flat. That’s only half a second slower than the high-performance AMG SL 63, which has the same engine and is around 400 pounds lighter. The Bentley Continental GTC is faster by almost a second, but it does have 771 hp on its team. The 416-hp Lexus LC 500 Convertible does the dash in a more-than-respectable 4.6 seconds. Think of the Maybach SL as a grand tourer and the AMG SL as the more sporty iteration.
Because this is the poshest SL there’s ever been, standard features also include an adaptive suspension with active hydraulic body roll stabilization, as well as rear-wheel steering to enhance agility and maneuverability. Driving modes are Comfort, Maybach, Sport, and Individual (a slot for drivers to make their own combination of steering, throttle, transmission, and suspension settings).
<h3>Fuel Economy</h3>
We’ll update this section when official information comes through, not that this will be a big issue for a Maybach SL owner. For a ballpark figure, the SL 63 achieves 16 mpg in combined city/highway driving. To compare, the LC 500 returns 18 mpg combined.

Curated Exterior

Exterior

Red or white paint &#8212; those are the standard, no-cost choices. With a black roof. Plus a black hood with the option of multiple Maybach badges &#8212; the marque’s equivalent of a Louis Vuitton design. But add $9,900 to the budget, and it opens the door to dozens of Mercedes&#8217; exclusive Manufaktur colors in a wide variety of hues. A Maybach grille treatment and substantial 21-inch alloy wheels are standard. Speaking of wheels, we like the multi-spoke design in particular &#8212; they’re a $5,000 option, but what buyer is going to balk at that?

FAQs

Our Favorite Features and Tech

Favorite Features

Massaging seats 
If you can’t be cosseted in a Maybach, even if it’s a 2-seater, then what’s the point? These are also heated and ventilated, and come with more cushioning than their AMG counterparts (which we’ve found to be extremely comfortable). The steering wheel is heated as well.
Burmester audio 
We’re huge fans of this setup, having experienced it in other Mercedes-Benz vehicles. A 17-speaker/1,220-watt surround-sound system is standard in the Maybach SL.
Airscarf 
A Mercedes-Benz innovation that has blessed several of its soft-top cars over the years. This standard feature in the Maybach SL emits warm air from vents in the seats near your neck. We like how you could still have the roof down on those crisp, clear winter days.
Magic Vision Control 
Admittedly, this sounds a lot more impressive than it really is, but we still like how the windshield washer fluid comes out of the wipers instead of just spraying everywhere from a set of jets. This is another Mercedes-Benz innovation.
Powered roof 
With three layers to keep the cabin suitably hushed and insulated, the roof will deploy at speeds of up to 37 mph and take about 15 seconds to complete its operation.
Biometric authentication 
Using a fingerprint sensor, the Maybach SL can recognize various drivers and load pre-saved settings like a favorite radio station. It will even recognize voices.

GMC Sierra 3500 for Sale in Longmont, CO

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Used 2023 GMC Sierra 3500 AT4 w/ AT4 Premium Plus Package

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