Changing from 10R22.5 tires on 7.5" rims to 11R22.5 tires on 8.25" rims, Is this advisable?

[Mercuric Mind]

Hi All,
I'm looking for some advice on changing from stock 10R22.5 tires on 7.5" rims to 11R22.5 on 8.25" rims. I have a 2001 Freightliner FS65 chassis with a Thomas coach. Will there be issues with tire clearance and wheel spacing between the duals?

Thanks,

 

[nikitis]

going from 10R to 11R is not an issue but not sure about the rim value.

When you say going from 7.5" to 8.25" are we talking about width of the rim? If so it should not be an issue.

 

[Mercuric Mind]

going from 10R to 11R is not an issue but not sure about the rim value.

When you say going from 7.5" to 8.25" are we talking about width of the rim? If so it should not be an issue.

Yes the 7.5", 8.25" is rim width. It is less expensive to get new rims in the 8.25" and there are more tire choices in tire size 11R22.5

 

[BamaBus]

Hi All,
I'm looking for some advice on changing from stock 10R22.5 tires on 7.5" rims to 11R22.5 on 8.25" rims. I have a 2001 Freightliner FS65 chassis with a Thomas coach. Will there be issues with tire clearance and wheel spacing between the duals?

Thanks,

On a truck I used to drive for work the rear tires would touch if one or both lost air pressure. I always checked the clearance between the tires as I walked in to work. There are other threads here that address the issues you may have.

 

[Ronnie-SKO]

As long as the new rims have the same dish, then you will be one inch closer between the duals. See what your clearance is now and subtract an inch. More then likely you will be fine.

 

[Mercuric Mind]

As long as the new rims have the same dish, then you will be one inch closer between the duals. See what your clearance is now and subtract an inch. More then likely you will be fine.

There looks like a lot of space but I will measure tomorrow in the daylight.

 

[Mercuric Mind]

As long as the new rims have the same dish, then you will be one inch closer between the duals. See what your clearance is now and subtract an inch. More then likely you will be fine.

I measured the distance between the tires at the bulge above the ground contact area. it is currently 2" so I will assume it would be 1" if I were to go to the larger width tire.

 

[magnakansas]

The big deal here is……. The tires should not touch. Consider that everything will weigh more also.

William

 

[Mercuric Mind]

The big deal here is……. The tires should not touch. Consider that everything will weigh more also.

William

Yes Absolutely, the tires should not touch or be close to doing so under loaded condition. As best as I can calculate, based on Accuride documents, https://www.accuridecorp.com/sites/default/files/resources/2024-01/W1.000 Rev. 10 Accuride Wheels Product Catalog.pdf, for my existing rims & tires and the proposed new rims & tires, there will be a change of spacing between the 2 tires from 1.44" with existing to 1.11" with new. A difference of 0.33". I measured the existing spacing at 2" so I think the documentation is looking at a widest case scenario. I believe this will be OK. Wheel/tire clearance in the wheel well will not be an issue either, as the height is not changing and the added width reduces the space from tire to chassis by only about 5/8". Now up front I have to look at the space between the tie rod end and the rim. The existing space is 1", the proposed new spacing will be 0.53" I believe this will be OK. Steering clearance at full lock existing is a lot and will not be an issue with the new rims and tires. Based on this I think I have convinced myself that it will be ok. Still, I reserve the right to be totally wrong. I have been known to convince myself of stupid things like converting a school bus into a RV. I may go to the local commercial tire shop and ask if they can "try on a pair" to visually check, but this will vary based on the tire a little bit. So my question now is am I off base on this?

 

[Ronnie-SKO]

Not off base at all, very good research. The tire shop may well even have some used tires and rims laying around that they could put on to confirm fit.

 

[Mercuric Mind]

Thank you ALL for your input.

 

[Mercuric Mind]

As an update. I ordered new tires from Simple Tire. com and It went very smoothly. I would recommend them. They will deliver to whatever shop you want.