2020 GMC Sierra 1500 mpg

Combined mpg, 2WD Reg Cab 140"

17mpg

16 city, 21 highway.
2 mpg below the median of 13 trucks (2020).
33 trims: 17 to 21 mpg.

Miles a yearGas, $ a gallon

12,000 miles a year. Gas $3.20.

13 trucks (2020), one trim per model: the cheapest with a rating. Median 19 mpg.

2020 GMC Sierra 1500 mpg by trim
Trim	Engine	Drive	City mpg	Hwy mpg	Combined	Tank, gal	Miles per tank	Cost a year
SLE Double Cab RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
SLE Crew Cab RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
Elevation Double Cab RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
SLE Crew Cab LB RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
Elevation Crew Cab RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
Elevation Crew Cab LB RWD	2.7L	RWD	20	23	21	24.0	504	$1,829
SLE Double Cab 4WD	2.7L	4WD	19	22	20	24.0	480	$1,920
SLE Crew Cab 4WD	2.7L 4cyl	4WD	19	22	20	24.0	480	$1,920
Elevation Double Cab 4WD	2.7L	4WD	19	22	20	24.0	480	$1,920
SLE Crew Cab LB 4WD	2.7L 4cyl	4WD	19	22	20	24.0	480	$1,920
Elevation Crew Cab 4WD	2.7L 4cyl	4WD	19	22	20	24.0	480	$1,920
Elevation Crew Cab LB 4WD	2.7L 4cyl	4WD	19	22	20	24.0	480	$1,920
SLT Double Cab RWD	5.3L	RWD	17	23	19	24.0	456	$2,021
SLT Crew Cab RWD	5.3L	RWD	17	23	19	24.0	456	$2,021
SLT Crew Cab LB RWD	5.3L	RWD	17	23	19	24.0	456	$2,021
SLT Double Cab 4WD	5.3L 8cyl	4WD	16	22	19	24.0	456	$2,021
SLT Crew Cab 4WD	5.3L 8cyl	4WD	16	22	19	24.0	456	$2,021
SLT Crew Cab LB 4WD	5.3L 8cyl	4WD	16	22	19	24.0	456	$2,021
Denali Crew Cab RWD	5.3L	RWD	17	23	19	24.0	456	$2,021
Denali Crew Cab LB RWD	5.3L	RWD	17	23	19	24.0	456	$2,021
Denali Crew Cab 4WD	5.3L 8cyl	4WD	16	22	19	24.0	456	$2,021
Denali Crew Cab LB 4WD	5.3L 8cyl	4WD	16	22	19	24.0	456	$2,021
AT4 Double Cab 4WD	5.3L 8cyl	4WD	16	21	18	24.0	432	$2,133
AT4 Crew Cab 4WD	5.3L 8cyl	4WD	16	21	18	24.0	432	$2,133
AT4 Crew Cab LB 4WD	5.3L 8cyl	4WD	16	21	18	24.0	432	$2,133
2WD Reg Cab 140"	4.3L 6cyl	2WD	16	21	17	28.0	476	$2,259
Double Cab RWD	4.3L	RWD	16	21	17	24.0	408	$2,259
4WD Reg Cab 140"	4.3L	4WD	15	20	17	28.0	476	$2,259
Crew Cab RWD	4.3L	RWD	16	21	17	24.0	408	$2,259
Crew Cab LB RWD	4.3L	RWD	16	21	17	24.0	408	$2,259
Double Cab 4WD	4.3L	4WD	15	20	17	24.0	408	$2,259
Crew Cab 4WD	4.3L	4WD	15	20	17	24.0	408	$2,259
Crew Cab LB 4WD	4.3L	4WD	15	20	17	24.0	408	$2,259

Fuel cost

2WD Reg Cab 140", 17 mpg combined.

Per year: $2,259
Per month: $188
Per mile: 18.8 cents
Fill the tank: $89.60

Best mpg: SLE Double Cab RWD, 21 mpg. $1,829 a year.
Top trim: Denali Crew Cab LB 4WD. $2,021 a year. $238 less than the 2WD Reg Cab 140".

Trip cost

2WD Reg Cab 140": 21 mpg highway
Trip	Gallons	Cost
100 miles	4.8	$15.24
300 miles	14.3	$45.71
500 miles	23.8	$76.19
1,000 miles	47.6	$152

Commute cost

Miles one wayDays a week

Per month: $163
Per year: $1,958
Miles a month: 867

2WD Reg Cab 140". 20 miles each way, 5 days a week.

Is 17 mpg good? No. Beats 7% of 2026 cars.

MPG by year

Sierra 1500: combined mpg of the cheapest rated trim, 2009 to 2026.

Sierra 1500 by year: price, hp, mpg, size

Rivals

2020 GMC Sierra 1500 and rivals
Car	Cheapest trim	Combined mpg	Compare
2020 GMC Sierra 1500	2WD Reg Cab 140"	17 mpg
2020 Ford F-150	XL 2WD Reg Cab 6.5' Box	22 mpg	Compare
2020 Chevrolet Silverado 1500	Work Truck Regular Cab RWD	17 mpg	Compare
2020 RAM 1500	Classic Tradesman 4x2 Reg Cab 8' Box	20 mpg	Compare
2020 GMC Canyon	2WD Ext Cab 128" SL	22 mpg	Compare
2020 Toyota Tundra	SR Double Cab RWD	15 mpg	Compare
2020 Nissan Frontier	S King Cab RWD	20 mpg

What this cannot tell you

EPA ratings. Your own mpg will differ.

Gas prices change by state and by week.

2 or more sources
1 source
Model-level, rule or estimate
Sources disagree

How values are checked