Blow Out What To Expect

If you haven't watched the Critical Factor, from Michelin, in the first post in this thread in the Beginning forum, you should, it could save your life!

I haven't had a blowout on a trailer... However, I have witnessed them. The last I saw was on monday and the tire exploded violently throwing the entire tire tread out, tore up the slide out. This was on the interstate and the truck was on the other side of the interstate heading south while I was heading north.

This was explosive.. the other one I witnessed was my friends fiver I was following and the tire just started throwing bits and pieces... it didn't come apart like the other one did... Now the blowout I had in my car.. It was pretty bad and I felt that one for sure.

Thanks!

Jeremiah

jamnw wrote:
I had my first blow-out back in early August.
I was going 50mph, windows up and it sounded like a shotgun. The trailer lurched toward the side that blew then straightened out. There was a lot of smoke coming from the blown tire too.

I was talking with a co worker about it yesterday. He said he had one blow going about 70mph and it was very scary. He said the TT jerked violently. I think he was lucky to keep it under control. I don't drive that fast when pulling.

You might point out to co-worker that if he has ST type tires as most TT do the tire Max speed is 65 so 60 would be a reasonable maximum normal driving speed.
Blowouts are usually the result of running on a tire that has lost much of its air. A TPMS can give you warning of air loss.

Blow Out What To Expect

On a trailer...not much.

I had so many blowouts and run flat/shredded tires Goodyear refused to warranty/sell any more of their ST tires on my GN trailers.

Lots of run flats as much of the miles put on my GN trailers were at nite. Generally a slight tugging on the truck (almost like trailer chugging) is the first clue then a passing vehicle may honk or use his flashers after he got in front of me. Or at nite a check in the mirror's shows a great big spark show that comes when the tire has worn down till the steel wheel rolls on the pavement at speed.
Day time ?? If you can'y see the side of the trailer your unsafe and in many state its required by law.
I live in those big side mirrors watching the trailer and traffic behind me.

If its a actual blowout you will hear it unless the driver is one of those brain dead types that plays the stereo on R for roar.

I've had a blowout on a tandem axle 5th wheel and a triple axle 5th wheel and there was no indication that either had happened, other than the sound. No difference in the way either 5th wheel pulled.

I had my first blow-out back in early August.
I was going 50mph, windows up and it sounded like a shotgun. The trailer lurched toward the side that blew then straightened out. There was a lot of smoke coming from the blown tire too.

I was talking with a co worker about it yesterday. He said he had one blow going about 70mph and it was very scary. He said the TT jerked violently. I think he was lucky to keep it under control. I don't drive that fast when pulling.

Tom/Barb wrote:

et2 wrote:
Anyone heard of this place?

http://www.shop.greatrvproducts.com/main.sc

They have a 10 tire for $499

They are who I ordered from, at that price, the system works great.

Thank you. I'm always a bit leery before ordering on-line. I will purchase tonight.

et2 wrote:
Anyone heard of this place?

http://www.shop.greatrvproducts.com/main.sc

They have a 10 tire for $499

They are who I ordered from, at that price, the system works great.

2500 Grunt wrote:

fj12ryder wrote:

Turtle n Peeps wrote:
A TPMS will NEVER save you from a blowout.

EX:
A blowout is: the tire is good, good, good, good, BOOM, not good.

A TPMS is good for tires that get a puncture in them and go flat and shred. Only had one of those in my life in my life. Only felt a slight vibration in the steering wheel and saw a little rubber coming off.

Never had a blowout on my trailer and I have ran ST China tires all my life.

I think I'd take exception to that statement. A blowout is an explosive decompression of the tire. It can be caused by many things including a build up of heat, perhaps due to the tread separating. It gets too hot, and BOOM. A TPMS will alert you to excessive heat, perhaps before the tire goes BOOM.

What about an over inflated tire with over torqued lug nuts running faster than a ST tire can handle in 120 degree air temp? Could even add a over loaded axle to it too.

None of the thousands of failed tires from the field, I inspected in my 40 year failed simply because of over-inflation. Most tires can handle many times the inflation on the tire sidewall if not damaged from abuse.

If properly inflated (sidewall max) even exceeding the 65mph limit in Phoenix is not enough in the short term to cause a Blowout. High heat from these conditions can cause accelerated aging (heat affects are not linear but double each 18F). Such aging can lead to degradation of rubber elasticity which then can lead to a separation of the belts from the body which is not a "Blowout".

" Blowout A Real Life Experience
In the previous post I covered Run Low Flex Failure, RLOF, and how there were telltale sign or physical evidence that while each taken individually are just circumstantial in nature but when take an a whole make a very strong case for the tire having been operated for a number of miles at very significant air loss. In this post I want to walk you through the thought process of a forensic analysis of the evidence that is available and show how an opinion or conclusion is reached.

First I need to tell you that I have not had the opportunity to personally inspect the subject tire, but there is a YouTube video and I will show you some shots from the video and tell you what I see in these shots. Second I cannot tell you about the individual as I have had only limited correspondence about this tire failure but according to statements in the video they called it a "Blowout", said they had checked the air pressure in the morning and had only driven about 45 miles before the loss of air occurred.

So lets see what the pictures show. I have highlighted the area of interest in each picture. In pic #112 we see in the yellow area signs that the interior of the tire was worn from abrasion on the inside of the tire under one side of the tread rubbing on the inside of the tire above the wheel. This occurs at 0 psi but takes more than the half mile it takes to come to a stop to wear this much. Also the tire must still be in one piece such that the tread can uniformly contact the lower interior of the tire so the wear occurred before the tread part of this tire broke away. In the red area we can see a few dark holes where the body cord has melted and shrunk back into the tire structure. This occurs when the body cord exceeds 390°F. To put this temp in perspective properly loaded and inflated tires may get to 160°F and ultra high speed tires such as seen at the Indianapolis 500 may see 200° to 210° but rubber starts to come apart an just a little more than that.


In pic 108 is another view of the same location of melted body cord. If the cord had simply failed due to high pressure the cord would be frayed. Also note the nice circumferential line the failure took. More on that later.


Moving on to pic 057 note the areas circled in red. An alternate view is seen at the arrow in pic 426. Now if we compare the loss of the ridge that is easily seen in pic 121. What this means is that the upper sidewall was in contact with the road surface for a number of miles and the outer edge of the sidewall "Scuff Guard" raised rib has been completely worn down. What we do not see is the lettering of the "Scuff Guard" worn away so we know that the wear was not due to the trailer being repeatedly parked against a curb.


+++++++++++++++++++++++++++++

Now I am sure some are wondering how I can tell the difference between running a tire at 5 psi vs 0 psi. Well here are some shots from an experiment I ran myself a few years ago.


This first picture here on the left shows the wear of the upper sidewall that occurred in only 3.9 mi while the tire had a minimum of 5 psi cold inflation. This is a bit like the wear on the RV tire sidewall
The next picture is of the interior of the same tire. You can see the nice circumferential crease/crack that has formed. This tire did not generate enough heat to melt the body cord as I was driving at less than 10 mph for the 3.9 mile test. That crease is at the location up the sidewall similar to where we see the circumferential failure in the "Blowout". Note there is no contact between the inside of the tread and the inside of the tire above the wheel as seen in the RV tire.
If you look at some of the examples shown in the previous post you will note that many show the same nice circumferential failure line.
Here are some examples that I use as ref pictures to help me understand the Root Cause of a tire failure.

Here are pictures of melted body cord, broken body cord and the holes sometimes left when the cord heats up and shrinks as it melts.
I hope this helps you see how easy it is to be mistaken when you think the failure is because of a defective tire when in fact the evidence shows the tire lost air, the RV continued down the road at normal highway speed and after a few miles the tire "blew out". The only way to have some warning and to protect yourself against this all too often type of failure is to have a TPMS which will warn you as soon as the tire looses 10% of its air.


Bottom Line: I do not think this tire was "possibly defective" or a "crap tire". It did not "fall apart for no apparent reason". It came apart because it lost its air and the operator did not know till too late. "

The above quote is from a blog on RV tires.