Even though I just bought my truck I have to wonder about replacement tires. I noticed that there are very very few options in the 235-75-17 tires that it came from the factory with. I am wondering what everyone on here has done. I know it will fit larger tires but that will also alter the final drive ratio and could cause the transmission to shift at the wrong times and would make the speedo inaacurate. I know that a small size change would cause a very veyr small change in those things but I plan to keep this truck for a while and don't want to cause any unnessesary stress on the trans.

 

You can easily go to the optional size 255-70-17. Based on revolutions per mile, the difference based on the data on the TireRack site is only 1%. It is not enough difference to cause any concern and depending on which way your speedo is off, may even help...

 

You're likely to see as big a difference in the true size of different brands/styles of 235-75 as you will in going to a 255-70 (as far as the height of the tire).