Need Help With Tire Sizes

[Dust N Bones]

I never did understand all the different numbers in a tire's size. Can someone tell me if 215/60/15 are close to 215/60/16? I have new snow tires that are 215/60/15's and I want to put them on a car that has 215/60/16's. Will that work?

I know the wheel sizes are different but I had the 215/60/15 snow tiires on a car that came with 215/55/16 tires and those two sizes are as close to an exact match as you can get.

[szh]

I never did understand all the different numbers in a tire's size. Can someone tell me if 215/60/15 are close to 215/60/16? I have new snow tires that are 215/60/15's and I want to put them on a car that has 215/60/16's. Will that work?

I know the wheel sizes are different but I had the 215/60/15 snow tiires on a car that came with 215/55/16 tires and those two sizes are as close to an exact match as you can get.

Hmmm, no, this will not work, unfortunately. The final number is the wheel rim diameter, and 15" tires cannot fit on 16" rims and vice-versa. Even if you could "stretch" the tire some to make it work, which is unlikely, the bead of the tire would not sit properly on the rim and could lead to blowouts and fatal accidents at any speed.

Z

[pito11213]

The 215 is the width of the tire.

the 55/60 is the height of the tire aka how much rubber top to bottom.

and the 15/16 is the rims size.

Get 225 wide they look better at the bare minimum. And I think 55 tall with the 15 rim.

[elwesso]

Pito you want a taller, skinnier tire for snow tires......

[Dust N Bones]

Hmmm, no, this will not work, unfortunately. The final number is the wheel rim diameter, and 15" tires cannot fit on 16" rims and vice-versa. Even if you could "stretch" the tire some to make it work, which is unlikely, the bead of the tire would not sit properly on the rim and could lead to blowouts and fatal accidents at any speed.

Z

I think maybe I didn't explain the situation good enough. I know the dfference between the 15" and 16" wheel sizes. See right now I have a 2001 I30 with 215/55/16 tires. I bought some old Infiniti 15 inch wheels last winter and snow tires from the tire rack size 215/60/15. Those two siizes match perfectly. Now I have a chance to buy a cheap '95 Taurus SHO that I would like to use as my winter car so I don't have to driive the I30 in the snow. The SHO comes with 215/60/16 and I want to know how close the 215/60/15 inch snow tires will be in diameter. And if they will be safe to use.

[Rex]

Are you saying the tires are already on rims? And you just want to know if the overall diameter is close enough for your speedo to be accurate?

[97Q45t]

Let's see,215/60/16 has 26.2 inches dia.215/50/16 has 25.2 inches dia.

The difference is 1 inch. Divide 1 inch by 26.2 inches, we get approx. 0.038168, which is about 4%.

Well, this's another way to say it:After you put your I30's snow tires on the SHO, driving in the snow and the SHO's speedo shows 100 mph then you're only doing 96.
Modified by 97Q45t at 10:57 PM 12/2/2004

[Dust N Bones]

Let's see,215/60/16 has 26.2 inches dia.215/50/16 has 25.2 inches dia.

The difference is 1 inch. Divide 1 inch by 26.2 inches, we get approx. 0.038168, which is about 4%.

Well, this's another way to say it:After you put your I30's snow tires on the SHO, driving in the snow and the SHO's speedo shows 100 mph then you're only doing 96.

Thank you that's exactly what I was looking for. So they're not too far off? Do you think it would be safe to put the 15" snow tires on the SHO in that case since the difference isn't that much? Or is 4% considered a big difference when it comes to tire sizes?

[97Q45t]

Thank you that's exactly what I was looking for. So they're not too far off? Do you think it would be safe to put the 15" snow tires on the SHO in that case since the difference isn't that much? Or is 4% considered a big difference when it comes to tire sizes?

My guess is it would be OK but I can't advice you on that because I neither own a set of snow tires nor drive in the snow. The 15" would cause more torque to be transferred to the wheel than the 16" does. So I guess it would be a little harder (maybe 4% harder ? ) to drive in the snow with the 15" snow tires than if it was with the 16" snow tires?

[IvoryJ30t]

here this should clear up tire sizing-

lets take 255/40-17

255 is the width of the tire in millimeters.

40 is the tires height expressed as a percentage of the section width.

17 is the wheel diameter in inches.

so, the tire is 255mm wide, and the sidewall is 40% of 255 tall. the tire will fit on a 17 inch wheel.

to figure out how tall the tire will be-

take the section width of 255mm and multiply by .40

you get 102mm. therefore, the sidewalls are 102mm high.

multiply 102mm by 2. you get 204mm. [you multiply by 2 because there are two sidewalls, top and bottom]

divide 204mm by 25.4 [conversion from mm to inches]

you get 8.03 inches [height of both sidewalls]

add 8.03 to 17. [because 17 inches is the size of the wheel]

you get 25.03 inches, which is the total height of the tire.

if you multiply 25.03 by 3.14, you get 78.59 inches. the distance traveled by the tire during one revolution.

[szh]

I think maybe I didn't explain the situation good enough. I know the dfference between the 15" and 16" wheel sizes. See right now I have a 2001 I30 with 215/55/16 tires. I bought some old Infiniti 15 inch wheels last winter and snow tires from the tire rack size 215/60/15. Those two siizes match perfectly. Now I have a chance to buy a cheap '95 Taurus SHO that I would like to use as my winter car so I don't have to driive the I30 in the snow. The SHO comes with 215/60/16 and I want to know how close the 215/60/15 inch snow tires will be in diameter. And if they will be safe to use.

Okay. My confusion was that I misinterpreted your original post (see the red highlighted numbers):

Quote »Can someone tell me if 215/60/15 are close to 215/60/16? I have new snow tires that are 215/60/15's and I want to put them on a car that has 215/60/16's[/quote]I made the mistake of assuming that you were going to use those 15" tires on the 16" rim, rather than changing the wheel entirely! Sorry about that!

Z

[szh]

And to answer your original question, yes, I also think it would be OK to do so. The diameter change is not bad. So, along as the tire load index is good enough for the Taurus weight, it should be okay.

Z