GMC: 2021: Sierra 2500 HD AT4, 6.6L Eng VIN 7

This is a LEMON manual, retrieved in 2025.

• Repair and Diagnosis
• Repair and Diagnosis, all links on one page (may load slowly, but easier to search)
• Labor Times
• Download .zip for offline use

This manual is identical to the manual for the following model variants, except for possibly the "Labor Times", "Fluids", and "Tire Fitment" pages:

• Sierra 2500 HD Base, 2D Pickup, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas
• Sierra 2500 HD Base, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas
• Sierra 2500 HD Base, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas
• Sierra 2500 HD Base, 2D Pickup, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas/Ethanol
• Sierra 2500 HD Base, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas/Ethanol
• Sierra 2500 HD Base, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control, Gas/Ethanol
• Sierra 2500 HD Denali, 6.6L Eng VIN 7
• Sierra 2500 HD SLE, 2D Pickup, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
• Sierra 2500 HD SLE, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
• Sierra 2500 HD SLE, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD, Automatic T/Case Control
• Sierra 2500 HD SLT, 4D Pickup Crew Cab, 6.6L Eng VIN 7, 4WD
• Sierra 2500 HD SLT, 4D Pickup Extra Cab, 6.6L Eng VIN 7, 4WD