Stock 15's & 16's rim/tire questions for 2k +

[RoninVon]

I have a 2000 Xls - and I notice on my truck I have the

P235/75/R15

and that on the XLT's they come with

P255/75/R16,

My question is, I am in need of a new set of tires - but don't feel like going with anything crazy, and just want something to fit the stock rims, but I have come across people selling the 16's from the same models.

My question is, would the wider tire and larger diameter (2.2 inches) which equals 50 rev/per 45mph make a difference on my

1. Handling
2. Gas mileage
3. Spedometer/Odometer

Also - wouldn't I be able to hook a computer up to the truck and re-adjust the tire sizes to configure the Spedo/Odomo?

 

[95Xsport]

I have P255/70/R15 and I have for two years and havent noticed any difference in handling or gas mileage. Im currently at about 18-19 mpg. I know my speedometer is ahead by about 3 mph, but it was before when I had P235/75/R15. You should have no problem