Tires

Fuel Max
Pros - Improved fuel economy, same wheels/rims, no change in vehicle track width, replacement tires widely available, steer, drive and traier tires all the same size (easier tire/retread management) no change in vehicle trade-in value.
Cons - No reduction in tire/wheel weight

Wide Base Tires
Pros - Improved fuel economy, reduced tire/wheel weight
Cons - New wheels required, wider axle to retain current track width, limited tire replacement availability, steer tires different size than drives and trailer tires (what to do with worn steer tires?), trade-in value of vehicle may be compromised due to "non-standard" tire/wheel/axle sizes.

I forwarded your question to Mike Beckett, President of MD Alignment. Mike knows more about tire wear than anyone I know.

"First you get a more effective transfer of loads to the steer axle with a set back vs a normal axle set. This does not mean more than about 500 lbs per tire in load but it is a more consistent transfer and this will have some minor effect. The larger effect is the turning angle on set back front axles. Most set forward axles turn 20 to 25 degrees as compared to 30 to 50 degrees on set back axles.

This increase in steering angle increases the "ackerman" effect on Toe when the vehicle in in a turn. A sharper steering angle and more toe on turns causes the vehicle to turn shorter circles and therefore it is more maneuverable but it does this at the expense of tire life. In my experience, on line haul trucks the net difference in tire life is about 10 to 15% between the two.

If you want to change this, adjust the steering stops on the axle to reduce turning angle and see how much you save. Just remember that the truck will require larger areas to turn around."

I don't know if you have steel or aluminum, hub piloted or stud piloted wheels. To be safe, you should checked the website for the brand and type of wheels you are running. I check one manufacturer's website and found a chart that gave wheel nut torques for the various wheels that they make. If you are still confused, contact the manufacturer through their website.