The 2026 GMC Sierra HD will offer only a few small updates over the preceding 2025 model year, however, customers will have a few new options when it comes to the exterior color palette.
Looking ahead, the 2026 GMC Sierra HD will offer two new paint options, namely Coastal Dune and Glacier White Tricoat. The pair of fresh paint options will replace Thunderstorm Gray and White Frost Tricoat in the heavy-duty truck’s lineup. Photos of the 2026 Sierra HD in either of the two new hues are currently unavailable.
Thunderstorm Gray (GNO)
White Frost Tricoat (G1W)
Coastal Dune is tagged with paint code G52, while Glacier White Tricoat is tagged with paint code G4J. As for the two outgoing colors, Thunderstorm Gray is tagged with paint code GNO and White Frost Tricoat is tagged with paint code G1W.
Thunderstorm Gray was initially introduced to the GMC Sierra HD lineup for the 2024 model year and was offered on most trims, with the exception of Denali and Denali Ultimate. Pricing was set at $495 price, with availability for all interior colorways. White Frost Tricoat was previously exclusive to SLT, Denali, and Denali Ultimate trims, priced at $1,095. As GM Authority covered previously, White Frost Tricoat was officially built for the 2025 model year as of April 28th, 2025.
Beyond the color changes, the rest of the Sierra HD lineup is expected to carry over largely unchanged. The powertrain offerings will once include the naturally aspirated 6.6L V8 L8T gasoline engine, rated at 401 horsepower and 464 pound-feet of torque, while the optional 6.6L L5P V8 turbodiesel Duramax generates 470 horsepower and 975 pound-feet of torque. Both engines will once again pair exclusively with the 10-speed Allison-branded automatic transmission, with configurations available in both rear-wheel drive and four-wheel drive.
Production of the 2026 GMC Sierra HD is currently slated to begin on August 11th, 2025. This schedule includes all cab styles: Regular Cab, Double Cab, and Crew Cab. Dealer configuration tools went live on June 12th, 2025, as GM Authority covered previously.
Comments
Revolutionary colors, wow, just what we needed in this color blind world. I wonder if the fancy names for those two tints help to distinguish a vehicle fitted this way from the other 90% of grey and white cars and trucks on the road and parking lots.
Why does the “SIERRA” badge in the image look so wonky? Like it was reapplied by a cheap body shop.
Why don’t you try putting the bright blue that you have on the 1500 series? Once the twenty five hundred and the thirty five hundred. It would be nice to have a bright color this is one thing that it really upset me when I bought my at4