* Driving conditions: City driving will yield significantly lower MPG than highway driving. Terrain (hills, mountains) will also impact fuel economy.
* Vehicle condition: A well-maintained engine and properly inflated tires will improve mileage compared to a neglected truck. Things like the carburetor, air filter, and overall tune-up drastically affect performance and efficiency.
* Driver habits: Aggressive acceleration and excessive idling will reduce fuel economy.
* Modifications: Any modifications to the engine or drivetrain (e.g., larger tires) will likely affect gas mileage.
Realistically, expect anywhere from 8 to 15 miles per gallon (mpg). You're more likely to see the lower end of that range in city driving or with a less-than-perfect truck. Achieving the higher end would require mostly highway driving and a well-maintained vehicle. It's highly unlikely you'll see anything better than 15mpg.
There's no single definitive answer; the actual MPG will depend on the specific truck and its use.
