How many miles per gallon does a 1991 Ford f350 get?
The typical miles-per-gallon for a 1991 Ford F-350 varies by engine and drivetrain. In general, gasoline versions average about 9–12 mpg in city driving and 12–15 mpg on highways, while diesel-equipped trucks tend to achieve higher highway fuel economy, roughly 16–20 mpg, depending on load. Four-wheel drive and heavy payloads will reduce MPG across the board.
In 1991, Ford offered two main powertrain families for the F-350: a large gasoline V8 (7.5L) and IDI diesel options (6.9L and 7.3L). Fuel economy is strongly influenced by drivetrain (2WD vs. 4WD), payload, transmission type, and overall vehicle condition. The sections below break down typical mpg ranges by engine type and configuration for stock, unmodified trucks from that era.
Engine options and typical MPG for the 1991 F-350
Gasoline engines
The following ranges reflect common, stock configurations of the era (primarily the 7.5L V8).
- 7.5L V8 gasoline, 2WD: approx. 9–12 mpg city; 12–16 mpg highway.
- 7.5L V8 gasoline, 4WD: approx. 8–11 mpg city; 12–15 mpg highway.
Gasoline-powered F-350s typically show noticeably lower fuel economy in city driving and with 4WD gear, especially when fully loaded or towing.
Diesel engines
The following ranges reflect common diesel options in that era (6.9L IDI and 7.3L IDI).
- 6.9L IDI diesel, 2WD: approx. 12–15 mpg city; 16–20 mpg highway.
- 6.9L IDI diesel, 4WD: approx. 11–13 mpg city; 15–18 mpg highway.
- 7.3L IDI diesel, 2WD: approx. 12–14 mpg city; 17–22 mpg highway.
- 7.3L IDI diesel, 4WD: approx. 11–13 mpg city; 16–19 mpg highway.
Diesel-powered F-350s generally offer better highway efficiency, particularly with lighter payloads and two-wheel-drive configurations. Real-world figures will vary with load, maintenance, and driving conditions.
Summary
For a 1991 Ford F-350, fuel economy depends heavily on the chosen powertrain and configuration. Gas models with the 7.5L V8 typically achieve roughly 9–12 mpg in the city and 12–16 mpg on the highway, with 4WD reducing economy further. Diesel models (6.9L or 7.3L IDI) tend to deliver higher highway mpg, commonly in the 16–22 mpg range depending on weight and drivetrain, but city mpg can be around 11–15 mpg, again affected by payload and gear. When evaluating a vintage F-350, check the exact engine, drivetrain, and any towing/load history to estimate real-world fuel economy accurately.
