Over inflating tires better mpg on long road trips?

2 questions fellas and gals, has anyone ever over Inflated tires for better mpg on long road trips? If so did it work? 2nd question is when I first bought big birtha from the dealership it was topped off and max mileage till empty was 511. Every time I top off now I get like 438 sometimes 440, anyone else experiencing this. Thanks.

Yes it works. I've never tried it on my rig but my Buick gets 35mpgs cuz of it. I doubt that that will work these massive tires but try it I'd be careful and only do like 5 psi more than whatever the door sticker says. If ur going somewhere hot, forget it. Don't do it.

Probably not worth it. I wouldnt risk possibly damaging the tires

your mpg is based on your previous tank. in the sand dunes you burn through a lot of gas. when i fill up afterwards, it always shows less than 200 miles to empty, yet its full with 36 gallons.

With over inflated tires you will see a slight increase in mileage. The down side of doing this is the tires will wear more in the center of the tread. The distance to empty is based on mpg's of the previous tank so after a tank of highway driving you should see more miles to empty.

If you really want to improve your mileage, change your driving habits. Slow steady acceleration, slow anticipated braking, tuck in behind a truck to improve aerodynamics, 60 to 65 MPH max speed.. These will lend you as much as 20% better fuel mileage while driving, far more than you can manage from over inflation..

Yup today i was getting 15.1 with cruise control on 65

Drive 55 and you will really see a difference if MPG is that important to you over any inflated tires concept.

If you "Can't drive 55" because you can't stand it then you might want another vehicle for long trips that gets better MPG, like a prius......

You better take caution, max pressure the tire is rated for, then how much over that pressure you go, then take in for expansion from driving heat, and summer heat, a little less in colder weather.
Your gonna have to set factory pressure, then measure pressure after driving, to calculate how much expansion, and its gonna be hard , because driving conditions are never the same, unless your gonna play with nitrogen, good luck, be safe.

Saved a buck fiddy on gas blew out a 800 tire the crash priceless.