2020 GMC Sierra: Sierra 2WD · 5.3L · RWD · 6-speed automatic · FFV
One configuration of the 2020 GMC Sierra as listed by our sources. Every figure below carries its source.
| Specification | Value | Source |
|---|---|---|
| Engine | 5.3L 8-cylinder (SIDI; FFV) | EPA fueleconomy.gov |
| Displacement | 5.3 L | EPA fueleconomy.gov |
| Cylinders | 8 | EPA fueleconomy.gov |
| Fuel type | Flex fuel | EPA fueleconomy.gov |
| Transmission | 6-speed automatic | EPA fueleconomy.gov |
| Drivetrain | RWD | EPA fueleconomy.gov |
| Combined economy | 16 mpg (14.7 L/100 km) | EPA fueleconomy.gov |
| City economy | 15 mpg (15.7 L/100 km) | EPA fueleconomy.gov |
| Highway economy | 19 mpg (12.4 L/100 km) | EPA fueleconomy.gov |
Provenance & verification
- EPA fueleconomy.gov · US Government public data
Source checked: October 12, 2026
Data verified: October 12, 2026