Tire Sizes....???

[ashx2]

The tires that were on my '72 when I purchased it have gone south on me. Tire sizing is not exactly my comfort zone and don't know a lot about it. The current tires I have are P275/60R15. I have a neighbor down the road that has some tires that are P265/70R15..... What will be the difference, the height of the tire? Or how does that work? I'm assuming that the 15 is the size of the wheel itself, so that should be a doable thing.....or am I off base on this? Thanks

[bigmac73]

https://tiresize.com/converter

try this , I am thinking they will be the same since you are going bigger on the sidewall but less on the width

[67C10Step]

Losing not quite half an inch in width and gaining just under and inch in sidewall height.

275 mm width to 265 mm width

The sidewall height is the next number as percentage of width, 275 x 0.6 = 165 mm

For the 265/70-15 the sidewall is 265 x 0.7 = 185 mm

The overall diameter of the 265 tire will be 2x the sidewall difference so that would be (185-165) x 2 = 40 mm about 1.6" bigger diameter.

[ashx2]

thanks guys. I just need these to make it to where I can move the truck while it's being worked on. I'll eventually go with something better once all the important stuff is fixed and running again. I appreciate the info!

[HO455]

I was going to say the biggest difference between the 2 sizes would be the change in overall rear ratio. But for your current plan that wouldn't matter, unless the front end of the truck has been lowered a bunch.

[cj847]

Here is a tire sidewall chart I built trying to decide what diameter rim and tire size I want. This is the tire sidewall x 2 changed to inches. Add this number to the rim diameter for the overall diameter. The stock tire was about 28.8". Please note that not all diameter tires are available in all these sizes. This is just a guide.

What I haven't been able to find is what is the largest diameter tire you can run with stock suspension......I think it is about 30.5 to 31" but not sure.

I don't know how to upload an Xcel file so it is just a picture.

[Pro299]

cj847 I can tell you the max must be more than 31 because I have 31X10.5X15 on stock height and it fits fine (and looks just right IMHO).

[bigmac73]

40 years ago in high school I ran a 32 x 11.5 x15 on a 72c10with stock suspension and had no issues