Gas mileage for 1989 Ford F250 7.5l 460?

The gas mileage for a 1989 Ford F250 with a 7.5L (460 cubic inch) engine is notoriously low. You're unlikely to see more than 8-12 miles per gallon (mpg), and that's under ideal conditions. Real-world driving, especially with towing or hauling, will likely result in significantly lower figures – possibly even below 8 mpg. Many factors influence fuel economy, including driving style, terrain, vehicle condition, and tire pressure.