1991 GMC Sierra 1500 2WD (6.2L 8-cyl, Manual 5-spd, Diesel) MPG & Specs
Quick answer
The 1991 GMC Sierra 1500 2WD gets an EPA-estimated 18/23 MPG (city/highway) and 20 MPG combined, with an estimated $4,000/year fuel cost and 509 g/mi CO₂. Engine: 6.2 L 8-cyl.
The 1991 GMC Sierra 1500 2WD with the 6.2-liter 8-cylinder diesel engine returns an EPA-estimated 18 MPG in the city and 23 MPG on the highway, for a combined 20 MPG. This page summarizes the official EPA fuel-economy and emissions data for this configuration.
| Engine | 6.2 L 8-cyl |
| Transmission | Manual 5-spd |
| Drive | Rear-Wheel Drive |
| Fuel type | Diesel |
| Vehicle class | Standard Pickup Trucks |
| MPG — city | 18 |
| MPG — highway | 23 |
| MPG — combined | 20 |
| Annual fuel cost* | $4,000 |
| CO₂ tailpipe | 509 g/mi |
| EPA GHG score | — |
How efficient is it?
With a combined 20 MPG, the 1991 GMC Sierra 1500 2WD sits in the moderate range for fuel economy. That is about 31% better than the typical Standard Pickup Trucks of its era (15 MPG class average), making it one of the more efficient choices in its class.
Fuel economy and running costs
At about $4,000 per year in fuel (EPA estimate, 15,000 mi/yr), fuel is a major part of the cost of owning the 1991 GMC Sierra 1500 2WD. Over five years that is roughly $20,000 at today's prices — before insurance, maintenance, and depreciation.
Emissions
The 1991 GMC Sierra 1500 2WD emits approximately 509 grams of CO₂ per mile at the tailpipe. Lower emissions generally track higher fuel economy.
How to read these numbers
EPA figures come from standardized laboratory test cycles and are the same estimates shown on the vehicle's window sticker. Your real-world mileage depends on driving style, conditions, fuel grade, and maintenance. Use combined MPG and annual fuel cost to compare vehicles fairly.