I was running the G3's at 40PSI. Had been averaging around 20.9mpg with the stock Michelins, which I switched out to the 275/70/R18 G3's. Mpgs dropped down to 18.9. Didn't love the numbers, but felt the tire was a much better fit for the vehicle. Dropped down to 35PSI last week. Now averaging 21.9mpg. Great tire on and off road, in my opinion. May experiment at 33 in the future, which is where I was running the Michelins, but for now 35 feels like where these tires want to be and seeing an actual slight uptick in economy (which doesn't make sense to me, since I thought the higher tire pressure would actually result in better economy) makes these a winner in my book. Much better look for the truck, too.