Sierra 2500HD Denali Duramax LML 6.6

STORY

Sierra HD is the collective name for GMC's heavy-duty pickup line, which includes the 2500HD and 3500HD models, built for higher towing and payload than the light-duty Sierra 1500. The current T1XX-based HD trucks, launched for 2020, use the L5P 6.6L Duramax diesel with a 10-speed Allison or the 6.6L gasoline V8. They offer the AT4 off-road trim, the Denali luxury variant and advanced camera-based trailering systems.