Thanks very much for your replies. Nice friendly group here, it seems, and from the info

I have a 2005 2500HD gas, reg. cab long bed for a work truck. I usually haul around 500 - 1500 lb around in the bed all day in the city and get about 12 mpg.

Main interest is to increase my gas mileage. Has anyone in a similar situation found success with this, and how much of an improvement?

How did it work out for you, Tailspin?

I have a 2005 2500HD gas, reg. cab long bed for a work truck. I usually haul around 500 - 1500 lb around in the bed all day in the city and get about 12 mpg.

Main interest is to increase my gas mileage! Has anyone in a similar situation found success with ...