Community Forums

dblair2116 · 08-05-2015, 02:25 PM

I would like to change from 12 R 22.5 tires to a 315 / 80 22.5 tire. Do I need to change rims from 8.25 to 9.0? Some dealers are telling me I can use these rims, others are telling me no, I have to go to a 9.0 rim. This is on our 2005 Allure. Anyone run into this issue or have some advice?

IASM · 08-05-2015, 09:38 PM

I think the preferred width is 9 but the Michelin site list a 8.25 to 9 as acceptable. My question would be why. The 315 is a very robust tire with a capacity of 9090 at 130 but it is also a lot harder to find then a 12:00. Does your front axle weight suggest a more robust tire? I am going from a 315 to a 365 but it is for capacity only and comes with limited availability since Michelin is currently the only maker of the tire.

Mr_D · 08-05-2015, 09:45 PM

Most tires have a preferred wheel width and an secondary one. With the secondary one they might even derate the tire due to the narrower or wider width. The tire charts will have that info but you have to dig to find it.

stuhly · 08-05-2015, 10:43 PM

I used to run 315 tires on trucks and we got better mileage out of the tires with 9 inch rims over the 8.25.

Smitty77 · 08-06-2015, 07:47 AM

Your profile shows an Allure 40' 470. You might check the tables for your weight, and find that you can safely downsize from 12R's, instead of upsizing. Or perhaps at least for the front axle. (Our 40' 04 Allure, High Cascade with two Drivers Slides, would allow us to safely downsize to the next size tire down for the front axle. The rear weight, drive/tag, were too close to the top range of the next size tire down to feel comfortable doing so. And I have not done so, as we hope to get another two years out of our 12R's XZE* set of shoes

!

I also believe I remember reading that another CC owner with with he Continental RV tires, and that they were a bit narrower the the Michelins, for the same size diameter tire. (Memory may be off on this, think it was George B. on the Yahoo CC User Group. You might search via Goole via 12R or 315's and Country Coach - and find more info that way. It's been a topic for well over 10 years, on the options available.)

Michelin TCI centers, and Les Schwab are two tire dealers that keep coming up as being top notch to work with. I've also had good luck with Park House out of Southern California.

Best to luck to you,
Smitty