Tire Replacement

[Jon Wehrenberg]

Brian,

My comment about ELT batteries was made to illustrate Peter does do certain things that are time related even though the product is far from "used up".

Our tires are as critical as an ELT battery.

I wrote to Michelin and posted their response, verbatim. I can't find the post but it is here somewhere on this forum. But I did read the Michelin warrany. To explain further your excellent analysis of what everybody offers for warrany, Michelin is very specific in saying motorhome tires have a warranty up to five years.

They explain a few things that may help explain why their posture on five years compared to seven for commercial applications. Look for their warranty. In it they state that waxes and emolients migrate to the surface of the tires via flexing (as in use) and those compounds will help prevent the drying and cracking of the sidewalls (my words). We of course fail on that point. Secondly in the warranty booklet they also point out that for storage we have to raise the tires from the floor and keep them in a cool dry environment. We likely fail on that point. If we were to do those two things I would support Peter's posture 100%.

I personally would rather was money to prevent the potential harm that could occur due to a failed tire. We cruise at highways speeds often only a few feet from other motorists. We do not exercise our tires regularly, and I doubt if anyone except Dale takes the weight from their tires. Should one of our tires fail the good news is that our only cost is a roadside service call. More likely we will tear something up, and potentially we can have an accident.

Everybody needs to decide what they want to do based on whatever information they can glean from all the sources.

But to compare our bus tires with plane tires or tires on cars is not realistic. I calculate my plane tires are compounded for resistance to aging and not tread wear, unlike our bus tires. My tires might get 600 to 1000 landings, and might get 1000 to 1500 miles out of them. But they do not seem affected by age.

My car tires do not age well because as they age they seem less quiet and they lose the soft ride they offer when new. But they don't show signs of age indicating they are formulated different than the bus or plane tires. My point is that I Michelin wanted to sell more tires they would claim tey lasted seven years or ten years instead of saying five years, knowing we will shop for the cheapest that will make it for five years without blowing out.

[truk4u]

Hmmm, you have a blow out and take out the car next to you causing injury or death! At your court date and/or trial, the Attorney accuses you of negligence since the entire RV industry uses the magic 5 year date and your tires are older than the 5 years. When the jury is done with you, you no longer can afford the bus, the cars, the planes, the house and all those goodies near and dear to you and hopefully your not doing time. Remember, you must really be rich since your driving this Prevost.

Just a little tidbit to think about boys & girls....

[BrianE]

Jon,

The only point of my post was to illustrate there is no relationship between a warranty period and tire replacement criteria (which is a good thing, Tom). The Michelin Service Life Booklet and Bridgestone's How Old is Too Old Brochure are not warranty documents but are published to assist the tire user is determining when to change a tire. Michelin's only reference to replacing a tire based on age appears in their Service Life Booklet:

It is impossible to predict when tires should be replaced based on their calendar age alone. However, the older a tire the greater the chance that it will need to be replaced due to the service-related evolution or other conditions found upon inspection or detected during use. While most tires will need replacement before they achieve 10 years, it is recommended that any tires in service 10 years or more from the date of manufacture, including spare tires, be replaced with new tires as a simple precaution even if such tires appear serviceable and even if they have not reached the legal wear limit.

A simular quote from Bridgestone's "How Old is Too Old":

RV users, for example, often put no more than a few thousand miles on their tires a year. Their tires may need to be replaced because of age long before their treads are “worn out.” Is a 10-year-old tire too old? Probably. Is a 6-year-old tire too old? Maybe. Have your tires inspected. The age of your tires, along with their overall wear, condition of sidewalls, etc. are all factors your tire dealer will take into consideration when inspecting your tires and advising you on tire replacement.

I agree it is not realistic to compare our bus tires to other applications. BUT, as in ALL tire applications, tire condition, ride performance and environmental exposure are major considerations for deciding whether or not to replace a tire.

As always MOST of us will defer to your conservative and thoughtful advic. You will remember however that you have occasionally admitted that if you do not have the answer for a question you will make one up. In this case it appears you may be trying to justify your personal tire change criteria. I for one, would replace my tires at 5 years in an instant if you could offer evidence that age should be the determining factor in making that decision.
Incidentally, for a guy that is so darn careful about tire condition, it amazes me that you would expose the lovely Di to the lurking unknowns of Chinese tyres

[garyde]

As on so many forums, there is plenty of opinions. The general concensus here is 5 years is a good time to replace tires when considering replacing tires. In deference to Brian, one can debate , pull out charts, take testimonials and more, but when your on the side of a freeway, crawling under your RV with traffic 2 feet away from your head, the thought came into my brain 'maybe I should have replaced all of these damn tires after the 1st one blew out!' Penny wise, pound foolish.

[Coloradobus]

I have been told that tires while in motion generate a compound that protects them from UV rays. Sitting, as most of coaches do, and they aren't on the road daily, weekly, monthly like a charter coach, the UV devil will decay the rubber. Parking your coach indoors will help slow this process, so I follow the 7 year rule that is also not documented.
Our coach is a 1999 shell, and we just spent $$$$$$$$$ at Prevost Factory sevice center in St Nicolas, Quebec. We replaced many rubber products under the coach, rubber bushings, ball-joint boots, etc. These things didn't decay over night or even since we were last at Mira Loma---January 7, 2007. But no one there in January said anything other than all looks good after the grease job. Hmmmm.
The last we need to do is "A" arm bushings.

[Jon Wehrenberg]

Brian,

Excellent point about the Chinese tires. I certainly gave a lot of thought about that, and that is why they are on the drive axle only. Right now they are holding air, they still ride smooth and don't have any balance issues, so I am optimistic.

If one of them fails it is probable I will not suffer any loss of control, but I may tear things up. It is a risk. FWIW the Michelins are 16 ply rated and the Double Coin are rated 20 ply. Both are DOT marked but I have no clue if that involves anything more than checking to see if they are round.

Coloradobus hit on one thing not previously stressed. I changed all air bags a short time back. They were about 10 years old, an age when some problems with air bags had appeared with not only me, but some other guys as well. When I removed them I planned to keep a couple for "spares". There was substantial cracking where they roll over the piston. My point is that stuff like our tires, air bags, and brake diaphragms are rubber and they age. Prevost's posture on air bags as expressed by Bill Jensen in Branson was to drive them until they fail, with no recommendation for life expectancy. I contrast that with the Prevost policy as stated in their manual that brake chambers should be replaced annually or every 100,000 miles, whichever comes first. My point being that unless and until we can get sufficient data we can only do what we feel is best for us and take our chances.

Right now all we have to go on is anecdotal evidence.

[win42]

So lets re-cap what we learned from Michelin, Jon, Brian et,all. As long as we suspend our Michelin tires from a strong cable in a dark cave at a constant 65 degree temperature and the cable does not break we will be afforded the maximum use of our Michelin Tires. Well thats simple enough to understand.

[jello_jeep]

So lets re-cap

Re-caps not allowed Harry

[Gary & Peggy Stevens]

These things didn't decay over night or even since we were last at Mira Loma---January 7, 2007. But no one there in January said anything other than all looks good after the grease job. Hmmmm.

Chris or Jim, When you were in Mira Loma getting your bus checked the first of this year, WHAT did you specifically ask them to do on your bus?

Did you specifically tell them to check all rubber components, ball joints, seals, gaskets and things like that, or did you just ask for a General inspection? Trying to understand how specific someone has to be to get things like that looked at?

Maybe the general Joe Bus driver, wouldn't want to know the rubber busings could have problems some time this year???

Gary S