GMC Sierra vs Rivian R1T

The Rivian R1T is the more efficient of the two: it reaches 87 mpg combined versus 68 mpg for the GMC Sierra, a 19 mpg advantage and costs about $250 less per year to fuel.

Across 4 measured categories, the Rivian R1T leads in 4. Figures are EPA test data, not manufacturer claims.

2015–2026

GMC Sierra

Standard Pickup Trucks 4WD · 274 configurations

68mpg combined (best)
All GMC Sierra specs

2022–2027

Rivian R1T

Standard Pickup Trucks 4WD · 91 configurations

87mpg combined (best)
All Rivian R1T specs

Head-to-head specifications

MetricGMC SierraRivian R1T
Best combined MPG68 mpg87 mpg
Best city MPG75 mpg94 mpg
Best highway MPG61 mpg80 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$1,100$850
Lowest CO2 output392 g/miNot available
Engines offeredSIDI, 3.0, SIDI; FFV, SIDI; with Sport ModeNot available
TransmissionsAutomatic (A1), Automatic 10-spd, Automatic 8-spdAutomatic (A1)
Drivetrains4-Wheel Drive, Rear-Wheel Drive4-Wheel Drive, Part-time 4-Wheel Drive, All-Wheel Drive
Fuel typesElectricity, Regular, DieselElectricity
EPA classStandard Pickup Trucks 4WDStandard Pickup Trucks 4WD
Years covered2015–20262022–2027
Configurations on record27491

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Sierra vs R1T: common questions

Which is better on gas, the GMC Sierra or the Rivian R1T?

The Rivian R1T is the more efficient of the two: it reaches 87 mpg combined versus 68 mpg for the GMC Sierra, a 19 mpg advantage and costs about $250 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Rivian R1T runs about $850 a year in fuel at its most efficient configuration, versus about $1,100 for the GMC Sierra — a difference of roughly $250 per year.

What engines do the Sierra and R1T offer?

GMC Sierra: SIDI, 3.0, SIDI; FFV, SIDI; with Sport Mode. Rivian R1T: no engine data on record.

Are they in the same vehicle class?

Yes — the EPA classifies both the GMC Sierra and the Rivian R1T as Standard Pickup Trucks 4WD, so they compete directly.

More Sierra comparisons

Comparison id: gmc-sierra-vs-rivian-r1t