Tires-19.5 v 22.5

[Mirada2005]

When it is time to renew tires, is there any benefit to change to 22.5 and alloy wheels?

Thanks
Les

[smlranger]

Would think if your chassis was factory equipped with 19.5's and the coach was built around that, there would be clearance issues with changing to 22.5's. There might also be issues with the transmission, etc.

I would certainly consult with the chassis manufacturer. Which chassis do you have.....Ford or Workhorse?

[Vegasdan]

Besides having to get your speedo recalibrated.

[gknott]

I think getting the 22.5 alloy wheels to fit your existing hubs would be you biggest problem and along with items mentioned by the other posters

[paz]

Chassis with 19.5" tires and 22.5" tires usually have different final drive ratios. That, combined with possible clearance problems (especially when turning), speedometer recalibration, the expense of new tires and the cost of new, aluminum wheels (approx. $2000) would (IMO) make the change not worth considering.

[Gary RVRoamer]

If your chassis was designed around 19.5" wheels, there is no real advantage to changing to 22.5". The bigger tires might run a bit cooler, but that's about it, and you would have to spend a good chunk of money to change - new wheels, recalibrate speedo and odometer, maybe rear axle and wheel well changes, etc.

Stick with what you have.

[Easyrider]

Another advantage I can think of the stay with the 19.5s is you probably have a spare onboard with the 19.5s, that's not so easy with the 22.5s.

[jimkate]

When should you change the tires?

I've heard that there's a chemical in tires that keeps the inner cords fresh that wears out in five or six years. Because of that, I've always thought that RV tires should be not be used more than six years-max., regardless of mileage or condition.

I've always thought that once the chemical is gone, the cords in the tire can age or rot from the inside, and you can't see that.

The DOT code on the tire will tell you the year the tire was made.

[Mirada2005]

Quote:

Originally Posted by smlranger Would think if your chassis was factory equipped with 19.5's and the coach was built around that, there would be clearance issues with changing to 22.5's. There might also be issues with the transmission, etc. I would certainly consult with the chassis manufacturer. Which chassis do you have.....Ford or Workhorse?

Right now we do not have a coach. The reason for the question is that we have been looking and the units we have looked at will require tires. I will probably stick with whatever size is on the coach we get.
Thank for the responses.
Les

[DAN L]

i would like to install a pair of michelin super single x one rv tires on the back of my moho. at this time they are only manufactured in 22.5. size: 39.7'' diameter, 525 rpm per mile. vs 245/70-19.5 33.3 diameter, 625 rpm per mile.

Michelin Americas Truck Tires X One® XRV® Page

Michelin Americas Truck Tires XRV® Page

i think there is just too much difference. i calculate that would be about a 16% overdrive. i would probably never get to 5th gear.
i have enough clearance in my wheel wells.
i don't really care about the speedometer error. i can make a correction table using my gps.
how would the allison hold up with this extra load?
what do ya'll think?
any ideas?
i gotta get tires next year.
just thinkin out loud...

[paz]

The big problem is it would be 16% overdrive ALL the time, which means acceleration will be waaaay slow.

[DAN L]

Quote:

Originally Posted by paz The big problem is it would be 16% overdrive ALL the time, which means acceleration will be waaaay slow.

what about fuel mileage? better, worse, the same?