2008 GMC Sierra 1500 2WD Trucks
- 6 cyl, 4.3L, 4-speed automatic: 15 city | 20 highway
- 8 cyl, 4.8L, 4-speed automatic: 14 city | 19 highway
- 8 cyl, 5.3 L, 4-speed automatic: 15 city | 20 highway
- 8 cyl, 5.3L, 4-speed automatic: 13 city | 18 highway
- Gas: 15 city | 20 highway
- E85: 11 city | 15 highway
- 8 cyl, 6L, 4-speed automatic: 13 city | 18 highway
- 8 cyl, 6.2L, 6-speed automatic: 12 city | 19 highway (premium)
2008 GMC Sierra 1500 4WD Trucks
- 6 cyl, 4.3L, 4-speed automatic: 14 city | 18 highway
- 8 cyl, 4.8L, 4-speed automatic: 14 city | 18 highway
- 8 cyl, 5.3L, 4-speed automatic:
- Gas: 14 city | 19 highway
- E85: 11 city | 14 highway
- 8 cyl, 6L, 4-speed automatic: 13 city | 17 highway (premium)
2008 GMC Sierra 1500 AWD Trucks (Denali)
- 8 cyl, 6.2L, 6-speed automatic (premium): 12 city | 18 highway
About Fuel Economy Ratings
A truck's actual gas mileage usage is never tested in the real world -- no wind resistance, no accessories running. To top it off, simulated speeds are far less than the average driver drives. Use EPA ratings to help you compare vehicles in a class, but don't count on them for an accurate projection of your actual gas mileage.
How Fuel Economy Ratings Are Calculated
