2005 GMC Sierra: Sierra 2500 HD 4WD CNG · 6.0L · AWD · 4-speed automatic · CNG
One configuration of the 2005 GMC Sierra as listed by our sources. Every figure below carries its source.
| Specification | Value | Source |
|---|---|---|
| Engine | 6.0L 8-cylinder | EPA fueleconomy.gov |
| Displacement | 6.0 L | EPA fueleconomy.gov |
| Cylinders | 8 | EPA fueleconomy.gov |
| Fuel type | Natural gas | EPA fueleconomy.gov |
| Transmission | 4-speed automatic | EPA fueleconomy.gov |
| Drivetrain | AWD | EPA fueleconomy.gov |
| Combined economy | 9 mpg (26.1 L/100 km) | EPA fueleconomy.gov |
| City economy | 8 mpg (29.4 L/100 km) | EPA fueleconomy.gov |
| Highway economy | 11 mpg (21.4 L/100 km) | EPA fueleconomy.gov |
Provenance & verification
- EPA fueleconomy.gov · US Government public data
Source checked: October 17, 2026
Data verified: October 17, 2026