GMC Sierra Cab Chassis MPG by year — every rating on record

The GMC Sierra Cab Chassis has a combined EPA fuel economy rating for 7 model years, from 2020 to 2026. Across those years its best rated version returned 17 mpg (2020) and its thirstiest returned 14 mpg (2021). The EPA record holds 23 configurations for this nameplate, most recently a Special Purpose Vehicle 2WD / Special Purpose Vehicle 4WD.

Year-by-year EPA ratings

Where it has stood in its class

Ranked against every other nameplate the EPA filed under the same class that year. The GMC Sierra Cab Chassis placed highest in 2021 at #4 of 4, and lowest in 2020 at #11 of 11. It spent 0 of its 7 ranked years in the top half of its class.

Every configuration on record

All 23 configurations EPA lists for this nameplate, newest first.

How the rating has moved between model years

Comparing the best-rated configuration of each year. 1 of 3 year-over-year steps improved the top rating.

What Sierra Cab Chassis fuel costs over a year

At the EPA's 11,500 miles a year, the 2026 GMC Sierra Cab Chassis burns 719 to 767 gallons depending on configuration. Below is what that costs at three pump prices, and how much more the thirstiest configuration costs than the most efficient one.

EPA’s own estimate for the 2026 model year is $3,900 to $4,150 a year in fuel, or $8,250 more than the average new vehicle over five years.

How it compares with other Special Purpose Vehicle 4WD

Across the 69 nameplates EPA classifies as Special Purpose Vehicle 4WD, the median best combined rating is 22 mpg. At 16 mpg the GMC Sierra Cab Chassis is 6 mpg below the median, which is worth about $686 a year at $3.50 a gallon.

• All Special Purpose Vehicle 4WD rankings — every nameplate in the class, best to worst.

Other GMC nameplates

Every GMC model compared → — all nameplates ranked by best combined rating, with what each one costs a year.