i currently have 265/75/16 on my truck 3.55 gears and a 4.6 i do all around driving city highway and some off road, and its kinda a dog. if i go 285/75/16 with my truck they will kill my gas mileage and have no power should i regear if so to what.

 

It's only an inch taller. But, if you think your truck is a dog an inch taller tire is not gonna help matters.

 

Wandell is right again.