Jonathan Hanson has a great article on his Overland Tech & Travel blog about the physics of tires and lifts.
To sum it up, larger tires and wheels do provide more ground clearance but will decrease performance in other areas. The additional mass and height of larger tires reduce acceleration and braking effectiveness. They also reduce the effectiveness of low-range gearing since taller tires are basically the same as adding taller gearing to your truck. This “regearing” through taller tires can also increase wear on drivetrain and suspension components.
Jonathan advocates a mild (rather than wild) approach when it comes to suspension and tire mods, as a rule of thumb no more than 2″ to 4″ of lift and one or two sizes larger for tires. Of course, research suspension and tire specifics for your own vehicle to determine what’s best.
Have a look at his article. It’s an interesting read.