Ron, had to laugh a little, but now being serious. I copied these two post
Tires and Burst Pressure - What Causes Tire Blowout? I think since so many of us drive our RV's for a number of years, some of us buy used ones, with original tires it becomes a concern. Most keep such low mileage on the units that we never reach the wear mileage on them. I do know that when I hit the 7 year mark or maybe sooner, new tires and of course alignment. guess I will be checking out big rigs now hahah
Also I put nothing on my RV tires. On my passenger cars I use all kinds of tire stuff, not to worried about tire life. Mileage usually takes care of them.
This is not so much of a question; I figured I'd write this to address some conventional misunderstandings related to tires and tire pressure. I've had at least a dozen people come up to me worried that if they exceed their manufacturer's recommendation for tire pressure and go up to the maximum sidewall pressure, that they may be more likely to have a blowout. This is not only untrue, but also leads one to be ignorant of the true cause of blowouts.
To start, what is burst pressure?
In my own words, burst pressure is the pressure needed to inflate a tire at which point it will physically burst. Generally speaking, tires will burst at a static pressure of around 200psi. This is a far cry from even the 51psi that the Eco's tires are rated for on the sidewall. What one needs to understand is that tire manufacturers have factored in a massive margin of safety in tire pressure ratings so that there is no possibility for an expensive lawsuit against them, so if they state you can run 51psi on your tires cold, you will be able to do so safely under normal road conditions. Keep in mind, a massive pothole will be likely to damage your tire regardless of pressure.
Moving on to the second part of this topic, what causes tires to blow-out?
In unexpected scenarios, I call this tire degradation. Tires have a "chemical clock" that allows them a finite amount of usable life in years, regardless of how they are stored. A popular showing on the show "60 minutes" (which can be found on youtube and has been posted here before) described this issue very clearly. A father had gone to a tire shop to have new tires installed on the family minivan so his son could drive off to Canada for a vacation with his friends after high school graduation. At some point during their visit, they had a tire blow out that caused the death of the driver and all passengers. It was later discovered using the date stamp on the side of the tire that the tire had severely exceeded it's usable life and should never have been sold. I don't recall the exact number, but the tire at the time was 6 or 7 years old.
To re-iterate, this guy had a tire blow out on their family minivan with what appeared to be a brand new tire, indistinguishable from a newly manufactured tire, that was actually manufactured 6-7 years prior and spent that many years on a shelf. The rubber compound on a tire begins to get weaker, more brittle, and loses its structural integrity over the years regardless of whether it's being used or if it's been sitting on a shelf. With the exception of defects, massive potholes, large punctures, and other "external causes," tires generally blow-out only due to age, regardless of pressure.
So, what can I do?
As if it's not bad enough that tires degrade on their own, excessive heat will accelerate this chemical degradation. By excessive heat, I'm referring to excessive sidewall flex/rolling resistance-induced heat. You can physically notice a significant change in sidewall temperature between a tire inflated at placard (car manufacturer's recommended) pressure and the maximum sidewall pressure. An under-inflated tire will not only cause a reduction in fuel economy and handling, but it will also significantly increase the temperature of the tire's sidewall due to constant flex and resistance, especially at highway speeds. This causes irreversible damage.
To maximize the life of your tires, inflate them to at least the placard pressure. Inflating them higher (but not exceeding maximum sidewall pressure), will help them last even longer, both with regard to tread wear and with regard to chemical degradation.
When purchasing new tires, check the date stamp on the tire to verify that it isn't an old stock tire. The following article shows you how to check:
Tire Tech Information - Determining the Age of a Tire
Replace your tires once they start to get old, despite how much tread life you may have remaining on that tire. A 7 year old tire is already dangerously likely to have a blow-out.
copied from http://www.cruzetalk.com/forum/12-wheels-tires-suspension/7733-tires-burst-pressure-what-causes-tire-blowout-print.html
I copied this one also
Blowouts are sudden, loud and unexpected, and when one happens, within seconds you can end up in a ditch or an accident. According to Michelin, there are approximately 523 fatalities and 23,000 accidents per year due to tire blowouts. Several common causes of blowouts exist, and the best way to protect yourself is to minimize your chances of having one. Watch the wear on your tires, keep them inflated at the proper pressure and check for damage if you hit a pothole or rock. Avoid curbs and check your tires for slow leaks
.Read more: http://www.ehow.com/list_6816077_common-causes-blowouts.html#ixzz2a2681xOT