"Ugly Betty" needs new shoes. First a little background. She is a 32 ft Regency with a GVW of 30,000#, 10,000# front, and 20,000# rear. She has 22.5x7.5 Alcoa aluminum wheels. The data tag shows original equipment tire size as 255/80R22.5 and the tires currently on the coach when we bought it are 255/70R22.5. According to tire charts the series 80 tires turn 551 RPM(revolutions per mile) and the series 70 turn 563 RPM. My speedometer is currently off about 6MPH at 70MPH.

I am considering three size tires:

• 255/70R22.5
• 255/80R22.5
• 11R22.5

The 11R22.5 tires are taller and have a RPM rating of 501. The recommended wheel width is 8.25 inches but they are approved by the manufacturer for 7.5 inch wheels. They are also rated 1,000# more than the 70 or 80 series tires. I think they would correct the speedometer. Also with a reduction in engine RPM I should burn slight less $4.00 per gallon, headed toward $5.00 per gallon, fuel.

Having said all this, I am looking for advice before giving some surely reputable tire salesman, that would not lie to me for nothing in the world, my hard earned $2,000 to $2,500.

Thanks in adviance
Nick

Without knowing which brand and looking at their charts, it is a little hard.

However, the 11Rs are likely to be cheaper and larger diameter. The larger diameter can be useful in the rear due to overhang issues, if you boondock. Or use my driveway.

There are also issues of wide tires having insufficient clearance where they meet the road on some dual installations, so look at that.

Consider the 70s or 80s up front, depending on the manufacturers' rec on wheel width and your needs re ground clearance.

My two bits and worth what you are paying. So said I would go with the 11R22.5 as they are available anywhere on the road. This is a standard truck size.

I would stay away from Michilan as they weather check like crazy in just a very few years. I like Kumho as they are one of the cheapest and after 8 years on our bus showed no weather checking. They just will not get the 300,000 miles you might get on Michilan.

And turning your engine over slower equals more MPG and that sure don't hurt.

I share Gary's negative feelings about Michelin, but for different reasons. My truck had bulging Michelins. Present owner of my last SOB had sidewall bulges on several tires that were only a few years old. No sidewall cracking. My Barth came with Michelins on the tag that were nine years old with no cracking or bulging.

Michelins need to be caressed all over before each trip. They find it very sensuous and will make them love you. It also lets you find any bulges before they become blowouts.

BTW, the MIchelin site has some very good advice on blowouts. No idea why.

quote:

Originally posted by Gary Carter:
So said I would go with the 11R22.5 as they are available anywhere on the road. This is a standard truck size.

Exactly...

Bill N.Y.