[n4byojim]

Originally Posted by n4byojim

Help us understand what "bad" means.
I have a '91 GMC Van with the same engine. On a good day, I get 15.5 to 16 MPG on the Highway - and 10 - 12 in town. That is normal/typical for a heavy, large vehicle. What are you getting?

You may get better mileage if you do the following:
1. Replace the air filter every 30,000 miles
2. Replace the spark plugs every 60,000 miles
3. Keep the MAXIMUM air pressure that your tires will allow.
4. pour (cheap) carb/fuel injector cleaner in the gas tank twice a year.
5. use semi synthic oil or full synthic oil in your oil changes
6. Pretend that an egg exists between your foot and the gas pedel - moving that much weight from a dead stop is killer on gas mileage.

Good luck