70r 80r Tires

[Ron & Kerrie]

We have a 1999 Dutch Star. The tire tag inside the motorhome reads that it should have 255/70r/22.5 tires for the rear tires. The tires on the motorhome are 255/80r/22.5. I'm just wondering if it makes a difference? Looks like the 80r tires have been on it along time. Why would they put 80r tires on it? Thanks for all your help.

["007"]

I'm not sure about this but aren't 80's wider if they are check the distance between the inside side walls of tires they may be rubbing together and will cause a wear problem prematurely.

[Ron & Kerrie]

007 I just went out and checked, the tires are not rubbing together. Thanks

[Gordon Dewald]

The 80 tires will be "taller" that the smaller 70 tires.

The first number is the tire width. The second number is the height of the tire as a percentage of the width. R would be a radial tire and the 22.5 is the rim size.

From what I have been reading having a larger tire on the tag than specified would increase the weight on the tag and subsequently move weight off of the drive tandems and on to the front axle.

[gruelens]

I found this calculator handy to compare tire sizes. Maybe it will help you with your concerns.

Tire Size Calculator - Compare Tire Sizes