Michlen Strikes Again

[Baby Bear]

It's been a while since I've made a posting but I want to warn again about Michlen tires and my latest experience. We blew two 255 80R 225 tires in three days. Had the correct tire pressure(100 #). Used crossover gages on the wheels. The unit is not overloaded, It's been weighed on all 4 corners, And there were no signs of roadhazard damage. We were going approx 40 mph when both blew as we were starting to leave at a traffic light. Milage on the tires was under 32000 and they had a manufacturing date of 04 & 05 of 2001. They were always parked on 2 x 8 treated lumber, so ground contact can't enter into the failure factor. Both blow outs were what is called a "zipper" type. Right where the sidewall and tread meets. WATCH OUT PEOPLE.I played by Michlens, rules and still lost!!!

[Baby Bear]

It's been a while since I've made a posting but I want to warn again about Michlen tires and my latest experience. We blew two 255 80R 225 tires in three days. Had the correct tire pressure(100 #). Used crossover gages on the wheels. The unit is not overloaded, It's been weighed on all 4 corners, And there were no signs of roadhazard damage. We were going approx 40 mph when both blew as we were starting to leave at a traffic light. Milage on the tires was under 32000 and they had a manufacturing date of 04 & 05 of 2001. They were always parked on 2 x 8 treated lumber, so ground contact can't enter into the failure factor. Both blow outs were what is called a "zipper" type. Right where the sidewall and tread meets. WATCH OUT PEOPLE.I played by Michlens, rules and still lost!!!

[CyberVet65]

Any tires on any RV that is 4 or 5 years old need to be replaced. Especially if running at 100psi. I know that milage should be a factor but look at many RV units that have tires that look perfect. Then get close and look at the exact spot that you had your blow outs. UV and lack of use destroys a tire from the inside out.
And five seasons and 32K isn't a lot of milage but indicates that the unit sits a lot. This is as bad as running the tire under pressure.
There are a number of threads here about "premature" failure of RV tires and those articles explain it a lot better than I can.
Chet

[Ray,IN]

If I read your post correctly, and understand correctly. Your tires are 4 years & 3months old. If I read and understand Michelin's website correctly your tires are warranted for 6 years. Did you have them replaced under the terms of the warranty? I just replaced the spare tire under my truck, it was 10 years old and still had some rubber "fingers" on the tread. The sidewalls were riddled with radial cracks, and it had one large vertical crack(this is the dangerous type). The tire may have had 100 miles on it. MY point is this: time and condition are the driving factors for determining when to replace tires, then wear. UV could not have caused these cracks in my spare because it was underneath my pickup since it was new with the truck in 1996. Tire mfgrs say ozone with non-use is the chief culprit, because the tire cannot flex and release the protective chemicals in the rubber.

[Brigadoon]

Baby Bear.
Which Michelin tire. XRV, XZA,...?

[Baby Bear]

These were XRV tires. I understand the XZA is being recommended as a replacement tire on RV's. As far as contacting Michlen, It's a waste of time. The two times earlier I had blown Michlen tires I was told they were overloaded and under pressure. Their other excuse is road hazard. These are their standard answers. I was also told by a qualified Michlen dearle to run at a Minimum of 100 PSI. I also have tire covers that are used when we park for any longer than a week. Like I said I followed all of Michlens rules and still got nailed.

["007"]

Did you show this Michelin Dealer the wheel weights of your coach for him to say put in the 100#. If you have them post them and your allowed axel weights, maybe we can come up with a answer for you. I've driven on Michelins for 5 different MH's never had a blow out. Did you get it weight at a CAT SCALE? Cost about $8. Please let us know. "007"

[Gary RVRoamer]

Baby Bear's tires are 4 years, 6 months old - a date of 04 2001 means the 4th week of 2001, not the 4th month.

And all XRVs built in 2001 are rated on the sidewall for at least 100 psi at full load (later models carry a 110 max). Bear may have been inflated more than required for his load, but was not overinflated for the tire's specs.

I'd make the warranty claim, Baby Bear. Preferably through the dealer where you bought them or the oe who recommended the 100 psi. Include your documentation on weight and a written affadavit that you carefully maintain 100 psi at all times. Maybe Michelin will give in for once.

[Tom and Patty]

BB,

Sorry to hear of your problems. Here is my take on these small 22.5 tires.

A 255/80R22.5 at 100 psi only holds 4975lbs. That gives a gross axle weight of 9,950. Your DP must be very close to that weight on the front axle. My Alpine is 10,300. Your tires were built in the 4th and 5th week of 2001. IMO they sould have been OK. But, a big BUT, the air envelope is so small on that size tire that you have no room for error on air pressure. Any small loss in air pressure on a tire maxed out, which I believe yours are, will be catastropic.
The zipper is indicative of a low air pressure or overloaded failure. Here is a link that dicusses zipper failures. You will probably only be interested in the "Revisiting the problem".

http://www.retread.org/PDF/ZipperFailures.pdf

[Baby Bear]

007- Was weighed at a FMCA convention so I feel comfortable with the numbers that came up. I only used the CAT scale for total weight , including tow car. One thing I should have mentioned earlier, the first one to blow was the outer LH dual and the next was the inner LH dual. As far as the dealer goes, he's a very good friend and familiar with my coach, The main reason he recommended 100 psi was because of the sidewall construction. In reality I could run less than 95# for my weight but at 100# it should make the sidewall more ridged. Tom & Patty, thanks for the related article. I'm going to print that!
As far as asking for warranty, You get the same answer every time and besides Iv'e got 4 new tires on the rear now, and, they are not Michelins'. Thanks everyone,but the main thing I wanted to do was just warn you about your possibilities when driving on Michelin tires. By the way, I also went up 1 size to be safer and it really stabelized the coach.

[Tom and Patty]

Lee,

It is good you went to a larger size as long as the duals are not rubbing and your wheels were wide enough. IMHEO those small profiles are just too little tire with no margin of safety for a DP.

What does your front axle weigh, and what is your newmar's gross axle weight? 95psi will only support 9610 gross axle weight.

["007"]

When I traveled to the Cat scales to weight the coach, I checked the tire pressure to see what it was after traveling 25 miles, tires were hot an the pressure had increased to over 115#'s. I had set all tires at 100# which was printed on the Newmar sticker. After weighting coach following morning reset tire pressure at 90# front, 85# rear according to Michelins' pressure tables. Improvement in ride and peace of mind. "007"

[Tom and Patty]

I don't know what size tire you have on your Newmar W-22, (235/80R22.5?) but how far did you travel to weigh the coach? What does your front axle weigh and what does the heaviest tire on the front axle weigh? Are you using these tables?

http://www.michelintruck.com/michelintruck/productguide...essure.jsp?tread=XRV

[Tom and Patty]

I just looked at Workhorse. Your front axle is 8000? At 90 Psi in front you will carry 8280. I'd bump that back up to 95-100. Gives you a bit more room for error.