Tires: putting higher profile tires on truck, stock rims, profile tires

Question
First of all, thank you for voluteering your time to answer this question.  I have 2003 Toyoto Tundra with Access cab, V8 and 17" stock rims.  The tires currently on there are P265/65R17 110s, my question is could I put a higher profile tire like a P265/70R17?  How would this affect my handling, gas mileage and overall effect on truck?  Thank you.

Answer
Ken,

There is usually enough room to go a little bit larger in both diameter and width, but the folks that do the measurements that confirm this keep this information secret.  They think it gives them a competitive advantage.

But small changes in sizing are not significant compared to what changing tires (brand, type, etc.) does.