Visit our Popular Forums

Estrange · 05-02-2017, 04:53 PM

Thanks for the links to the endurance posts.. I've read most of them previously. I would feel better when there are enough folks with a few years on them.

**Action** · 05-03-2017, 10:41 AM

Quote:

Originally Posted by Estrange

..... I am also aware that I have seen more ST tires fail, by several orders of magnitude, than passenger tires.

I understand everyone is going to a 16" wheel to still run a similar (overall) sized michelin tire, but I dont really want to spend a ton of money on new wheels if they are not needed. I've read that some folks were having to cut or resize their wheel wells with this wheel tire combo as well.

Much of the high failure rate of ST designed tires has to do with they are just barely or not capable of the job based on load. The RV industry and trailer in general are manufactured with the least expensive tire to get the vehicle sold. So the tire load capacity is nearly maxed out at max tire pressure when it rolls off the assembly line. There is little to no margin of safety, unlike cars and light trucks.

When tire replacement happens the owner just replaces old tire with new one that is exactly the same. Issues can occur later in life of the trailer. Like humans, trailers tend to gain weight. At some point the load of the trailer maxes out the capacity of the tires. Running the tire in any manner less than perfect leads to a tire malfunction.

For this reason moving to a 16" diameter rim greatly expands the load capacity! If moving to a 16" rim increases the capacity by 1000 pounds and the trailer load never even gets close to that number then an overloaded tire situation can never occur. Even to the point that the tire pressure no longer has to be set to the max.

I had a new (non-Airstream) dual axle trailer delivered to me that weight over 7000 pounds. At max tire pressure there was only 50 pounds of reserve before the ST tire capacity was maxed out. This never happens on cars and light trucks! Not even close. Add some tire neglect and it is an event that wrecks a day on vacation. The trailer industry does this frequently and as a tow truck driver I bet you saw the result of this event a lot.

Pay attention to the capacity of the tire and the actual load with a margin and much of that issue goes away no matter what letter is in front of the tire size.

>>>>>>>>>>>>>Action

Phoenix · 05-03-2017, 02:10 PM

Just my opinion...

XPS Ribs; expensive, but worth it (see attachment below).

For our single-axle Bambi, two new wheels and XPS Ribs were much cheaper than the cost of replacement ST tires and wheel well repairs from our GYM blowout. Also, one pair of Ribs outlasted two sets of ST tires, and with absolutely no problems (compared to three of five ST tires that failed).

I am so satisfied with the XPS Ribs that I just bought two more to replace the first pair.

==========

Note: Click to enlarge.

Click image for larger version

Name: zzzGYM-XPS RIB_Comparison_170504.jpg
Views: 94
Size: 68.6 KB
ID: 284657

Estrange · 05-03-2017, 07:23 PM

Thanks for the info!

I will say though that I was unaware that a tire for a 16 wheel help more capacity than a tire for a 15 wheel?

The Michelin XL's I'm looking at (from the title) are extra capacity 109 tires for a 15 wheel. Are similar tires on a 16 wheel several hundred pounds higher?

Bill M. · 05-03-2017, 08:15 PM

You would not be limited to similar tires with the 16" wheels. You can get tires all the way up to load range E at 80 psi so you can get more capacity. The problem with the 15" wheels is the limited availability of tires in that size. People go to the 16" size to increase load capacity and to keep from running a "passenger car" tire. They want one that says LT on it instead. Or a Michelin trailer tire like the XPS rib. I do not know the load rating or availability of tires similar to the 15" tires but in 16". The 15" Michelins suite my use just fine and have excess capacity for my trailer so I have not look at the 16".
I would actually like to buy a set of used Al 15" wheels from someone that is moving up to the 16" wheels if anybody is considering the change now.

waninae39 · 05-03-2017, 08:20 PM

my new 2017 AS port 22FB can with the Good Year Endurance

TheDuke · 05-03-2017, 08:28 PM

Go ahead and make the switch to 16" you wont be sorry. In a few years you wont be able to find 15"!

Estrange · 05-04-2017, 09:09 AM

The michelins in the title are LT tires in the XL load range, 109.. around #2100 per tire.

Is there a company that sells a balanced, mounted 16" wheel tire combo ready to mount? If someone can post a link, I would would be grateful.

I dont think we need more capacity.. but if the price is not horrible maybe I can swing it. I am also spending 200 on Centramatic's

xrvr · 05-04-2017, 10:35 AM

I believe that is incorrect, they are xl rated p tires..

**Action** · 05-04-2017, 12:06 PM

"I will say though that I was unaware that a tire for a 16 wheel help more capacity than a tire for a 15 wheel?"

Bigger tire more load capacity! It is a very simple no brainer move. This is another situation that bigger handles more.

As stated above more load capacity can be had in most rim diameters by moving up to a higher letter rated tire. Higher load rating become more difficult in smaller rim diameters. (Story) I bought a used 1974 Ford E 100. It was some what of a custom van from the factory. First off it was a black van with no windows. Ford didn't and I think still doesn't make a van in black. Too much surface area with a black color. Second it had 14" tires that were "E" rated. I didn't know anything about tires and when it came time to replace I wanted the same. Tire shop looked at me funny because the "E" rated 14" tire wasn't going to be cheap and was special order only.
I switched to a lower load tire.

Tires can be some what interesting to dial in. And I would not necessarily use what the factory used brand new. And once done, just repeat for all future times.

>>>>>>>>>>>>>Action[/QUOTE]

Estrange · 05-04-2017, 05:21 PM

The Michelin 235/75/r15 is an LT tire... LTX

http://www.michelinman.com/US/en/tir...r-ltx-m-s.html

Thats my point though... its not a bigger tire. If it was a bigger tire, it wouldn't fit the airstream. I do get the point there are more choices in a 16" wheel however. But I ran 15" 10 ply E rated tired for years on our 2008, the 16" fits in same spot, correct?

Alluminati · 05-04-2017, 09:29 PM

Quote:

Originally Posted by Estrange

The Michelin 235/75/r15 is an LT tire... LTX

http://www.michelinman.com/US/en/tir...r-ltx-m-s.html

I was fooled by this too. I have Michelin tires on my truck, and thought "LTX" indicated LT tires. Not so. Scroll down and check the size chart in the link. There are some LTX tires that are LT tires too, but most are P metric. Note also that the true LT tires have a lower speed rating and a much shorter warranty.

Estrange · 05-04-2017, 10:53 PM

Gotcha...

Our 2017 28 International has a dry weight under #6000... and max load of around #7600..

Even when boondocking, we dont max load the trailer, so #7900+ lbs of derated capacity with the 15" tires might be perfect for our load out of around #6700lbs

**Action** · 05-05-2017, 02:13 AM

Quote:

Originally Posted by Estrange

The Michelin 235/75/r15 is an LT tire... LTX

http://www.michelinman.com/US/en/tir...r-ltx-m-s.html

Thats my point though... its not a bigger tire. If it was a bigger tire, it wouldn't fit the airstream. I do get the point there are more choices in a 16" wheel however. But I ran 15" 10 ply E rated tired for years on our 2008, the 16" fits in same spot, correct?

In general given the same width a 16" tire is bigger holds more air than a 15".

>>>>>>>>>>>>Action