Thinking about going to some 265/70/17s on my dually since they are pretty plentiful in the used market.

Can the speedo be corrected for this and is it worth it? I thinks its only a 2.4% difference from the stock 235/80/17.

Any advantages/disadvantages to going to a 265? Its a smaller tire in diameter so I'm guessing that combined with a wider foot print may bring my mileage down.

 

yes you can have it changed. The dealer or some programmers can do it. I have 285/75's on mine and the speedo is 2 mph off the gps at 75, so it isnt that much really.

 

I was gonna do this on the 07 dually I had but I was told that they are essentially the same height as the stock dually tires, just a bit wider. They are very close, that's for sure....

 

If the dealer cant do it and you dont want to live with the 2-3 % difference I have heard good things about this
http://www.superlift.com/accessories/truspeed.asp

 

A Smarty Jr will adjust your speedo. I have mine dead on with my GPS. Oh, and as a bonus, you can adjust the program on your truck...