Tire replacement

gmc
1500

#1

i have 245/70-16 tires on a 2004 gmc c1500 sierra and would like to install 235/75-16 tires. will this cause great harm in the overall performance of the truck?


#2

You will not even notice the difference…The diameter is probably almost identical…


#3

Your first step ought to be to look for the vehicle tire placard - which on GMC trucks is located on the driver’s door or doorpost. That will tell you the original tire size and the proper pressure for that size.


#4

You are looking at a narrower and taller tire as the replacement. If they fit on the wheels OK, and I think they will, then you should be fine. You can expect your speedometer to have some error in the reading vs actual speed. This is easy to check with a GPS unit. Otherwise the narrower tire might have a bit less grip, but I’d bet hardly noticeable. In snow the new tires might do better, but tread design is a big part of snow traction so you’ll just have to see how they do when the snow flies.


#5

I agree…there is Powerdog.com to check the overall diameter of the two. I go from 265/65-17 to 265/70-16 in the winter. Though not a direct comparison to yours, like Caddyman said, the differences are insignificant if the ratios and treadwidth result in the same outside diameter; which yours look like they do.


#6

245/70-16 6.8" 14.8" 29.5" 92.7" 684/mi 60MPH 10000mi N/A
235/75-16 6.9" 14.9" 29.9" 93.9" 675/mi 59MPH 9875mi 1.3%

As you can see…the difference is .1 inches radius, and less than 1.3 % circumferance rolling distance …don’t worry as long as all are matched.