Originally Posted by Lakehouse 2
, A wheel that is available is the one used on the Ford F550. That wheel has the same bolt pattern (225 mm) and center bore (170mm), The differences to the F53 wheel is the rim width being 6" vs 6.75 and the offset being 5.35" vs 5.50". This is the wheel I am using with a 225/70/19.5 tire. The heavy truck tire guy would not mount
a 245/70/19.5 tire on the 6" wide wheel. He was adamant about this, in fact the 245 tire I wanted was much much more expensive than 225 tire I ended up with. I know using this smaller tire would not be ideal but we wouldn't be stranded if our wheel we become damaged
. When I was looking for the correct wheel I couldn't find any and the Ford dealer wanted $600+ and said it would probably take 6 weeks to come in. Good luck.
There are a couple problems with putting the larger tire on the 6inch wheel the first being that most tire manufacturers specify the 7.5 inch wheel as the required wheel, I did find one company that listed the 6.75 inch as the minimum wheel width. Putting the 245 on the 6 inch (too narrow) wheel can cause the tire to sit incorrectly in the bead area possibly leading to a sealing failure of the bead under load and sudden depressurization (blowout). The tire will also be distorted with the sidewalls bulging outward more than designed, generating excess heat in the tire, uneven tread wear and stress the shoulder of the tire where the sidewall and tread transition. The excess bulging combined with the shallower offset of the 6 inch wheel can also cause the sidewall to contact the sidewall of the other dual tire when mounted on the rear axle. I can tell you from experience, the heat generated in the two sidewalls from the tires rubbing each other WILL cause BOTH to fail simultaneously. I hate to think about what kind of fun that would be in Big Blue, when I had it happen before I was driving a loaded tow truck and the vehicle on the hook actually helped stabilize me. The tire guy that refused to mount the 245 on your wheel did you a big favor to keep you safe and saved you some cash on top of it.
By the way if you ever have to put the 225/6inch combo on the coach put it on the front right. It may give you a slight pull to the right but that is actually safer than a left pull. the right front is generally the safest position to change a tire on because you are farthest from traffic. Never use it on a rear dual, there is a little over a 1 inch difference in loaded diameter, this will cause the larger 245 to support the majority of the weight, possibly damaging the tire, or they may even rub in the middle...don't want that! Also with the smaller set on the front right it makes it easier to make it home before replacing the failed tire.
Here's to hoping you never have to use that spare