Based on data from 70 vehicles, 4,410 fuel-ups and 1,421,303 miles of driving, the 2021 GMC Sierra 2500 HD gets a combined Avg MPG of 13.17 with a 0.11 MPG margin of error.

Any Engine Type 6.6L V8 DIESEL (52) 6.6L V8 GAS (17) Any Body Style Extended Cab Pickup (1) Crew Cab Pickup (17) Any Submodel Base (2) SLE (7) SLT (9) AT4 (23) Denali (29)

Below you can see a distribution of the fuel-ups with 19 outliers (0.43%) removed.

Following shows the average MPG of each of the 70 vehicles in the system.

• «
• 1
• 2
• 3
• 4
• »

• AT4

  2021 GMC Sierra 2500 HD AT4 6.6L V8 DIESEL Automatic 10 Speed Crew Cab Pickup
  Added Oct 2022 • 82 Fuel-ups

  Property of scrabble890

• 14.3 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed
  Added Jul 2024 • 25 Fuel-ups

  Property of josterhout1

• 15.3 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD AT4 6.6L V8 DIESEL Automatic 10 Speed
  Added Sep 2023 • 175 Fuel-ups

  Property of SeB21

• 17.0 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLT 6.6L V8 DIESEL Automatic 10 Speed
  Added Jul 2024 • 8 Fuel-ups

  Property of jbhardman

• 13.4 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD AT4 6.6L V8 GAS Automatic 6 Speed
  Added May 2021 • 249 Fuel-ups

  Property of Buellx72

• 11.2 Avg MPG

• DENALI 2021

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed Crew Cab Pickup
  Added Dec 2020 • 124 Fuel-ups

  Property of rivcoinc

• 14.7 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed
  Added Apr 2023 • 98 Fuel-ups

  Property of bcfiremedic

• 11.9 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLE 6.6L V8 DIESEL Automatic 10 Speed
  Added Jan 2023 • 121 Fuel-ups

  Property of Croybal06

• 13.7 Avg MPG

• 2021 Sierra 2500HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed Crew Cab Pickup
  Added Jan 2024 • 57 Fuel-ups

  Property of Bost05

• 12.6 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD AT4 6.6L V8 GAS Automatic 6 Speed
  Added Jun 2021 • 197 Fuel-ups

  Property of gregnola

• 12.0 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLE 6.6L V8 GAS Automatic 10 Speed
  Added Oct 2021 • 162 Fuel-ups

  Property of bdamats

• 11.1 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLE 6.6L V8 GAS Automatic 6 Speed
  Added Nov 2024 • 12 Fuel-ups

  Property of Anticyclone

• 11.4 Avg MPG

• 2021 Sierra Denali HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed
  Added Dec 2020 • 199 Fuel-ups

  Property of LynnE24

• 14.4 Avg MPG

• 2500Hd GMC

  2021 GMC Sierra 2500 HD AT4 6.6L V8 DIESEL Automatic 10 Speed Crew Cab Pickup
  Added May 2021 • 149 Fuel-ups

  Property of jmgolden1978

• 14.0 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 GAS Automatic 6 Speed
  Added Aug 2021 • 56 Fuel-ups

  Property of drjim

• 12.4 Avg MPG

• 2021

  2021 GMC Sierra 2500 HD Denali Crew Cab Pickup
  Added Dec 2020 • 199 Fuel-ups

  Property of lampmant

• 12.9 Avg MPG

• BigTruck

  2021 GMC Sierra 2500 HD 6.6L V8 GAS Automatic 6 Speed Crew Cab Pickup
  Added Mar 2023 • 61 Fuel-ups

  Property of pmhanson

• 12.9 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD Denali 6.6L V8 DIESEL Automatic 10 Speed
  Added Jun 2023 • 25 Fuel-ups

  Property of egobuster1

• 15.0 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLT 6.6L V8 DIESEL Automatic 10 Speed
  Added Jun 2024 • 30 Fuel-ups

  Property of crossfamily

• 16.4 Avg MPG

• My Sierra 2500 HD

  2021 GMC Sierra 2500 HD SLT 6.6L V8 GAS Automatic 6 Speed
  Added Jan 2021 • 41 Fuel-ups

  Property of NGreen08

• 10.3 Avg MPG

• «
• 1
• 2
• 3
• 4
• »