Tyre blow outs

[CooperMedley]

We have a Lunar Solaris Twin Axle. Had two new Firestone Tyres 175/R14/86T
Fitted (front axle) a year ago (date on tyre 5012) so already 2 years old when fitted. On a recent trip the near side front tyre shredded on our outward journey and the offside front tyre shredded on the return journey. Both tyres had done less than 1000 miles since fitted. I have been towing for over 30 years and never had this type of problem before. Anyone else had a similar problem with this type of tyre with a similar date on tyre?

 

[WoodlandsCamper]

Are you sure you weren't exceeding the speed rating of 'T'. 118 mph does seem rather high though!

Joking aside, I wouldn't have expected age, manufacturer, speed or load to be a factor. The probability is that the front tyres would always pick up any punctures first as they are the ones rolling over any road debris first. Unfortunately without more information on how or what caused the shredding we can only put it down to sheer bad luck.

Did the problems occur on the same stretch of road in both directions?

Other possible causes - overheating brakes or wheel bearings on the front axle.

 

[Dustydog]

Do you still have the damaged tyres?
If so ask Fire stone to examine them for you. They could be part of a faulty batch.
Why didn't you replace the rear axle tyres at the same time?
Did you know the tyres were two years old when you bought them?
I assume a motor mover if fitted hadn't been left engaged?

 

[CooperMedley]

Thanks for the responses. The first was travelling North on the A11 dual carriage way after aprox 30 miles M11 & A11, the second was coming South (from Sheringham) around the Norwich By-Pass. I looked very carefully at the treads for signs of puncture but could find none.
The rear axle tyres had been replaced about 3 years ago and are still in good condition. The van was serviced in June 2015.
I will speak to my tyre supplier and ask him to send it back to Firestone for inspection.

 

[emmerson]

A few years ago I bought a pair of tyres for my 'van. When one punctured at about two years old, the tyre company would not repair it, as it was FOURTEEN years old! The matching one was only three years old. I now examine all new tyres for date before parting with any money.

 

[ProfJohnL]

If vehicle is designed to have four tyres, and one fails then the load of the vehicle is being supported by the remaining three. This can change in load can precipitate the early failure of another tyre if it's having to work much harder than it should do.

Of course the additional wear caused by the failure of another tyre may not be immediately obvious.

 

[Craigyoung]

We were on way down A1 other week heading to Dover when we stopped for 5 minute toilet break at a small service station when we noticed a man trying t change a flat on his caravan - he'd clipped the high kerb at the pumps and split the tyre ! He was flapping cos his jack said SWL at 1 ton ! But with a bit of help , he was sorted & very grateful in 1o minutes !!!!

 

[WoodlandsCamper]

He was flapping cos his jack said SWL at 1 ton ! But with a bit of help , he was sorted & very grateful in 1o minutes !!!!

Unless his van weighed over 2 tonnes then the jack was OK as he would only be lifting half the weight ie only one side of the van at a time. :cheer:

 

[Woodentop]

It tends to suggest that the 'van is running slightly nose down which puts excess load on the front pair. I would suggest some careful measurements to make sure the 'van is running level when hitched up.

 

[ProfJohnL]

It tends to suggest that the 'van is running slightly nose down which puts excess load on the front pair. I would suggest some careful measurements to make sure the 'van is running level when hitched up.

There is no requirement for caravans to 'run level' .

The caravan manufacture has certain regulations to comply with when designing their products. One is the standard hitch height when coupled to a saloon car is a nominal 385 +/- 35mm to geometric the centre of the ball. Provided the outfit complies with this measurement it is classed as normal. With permitted a 70mm range on the hitch height, the chances are very few caravans would actually be 'level'.

 

[Dustydog]

It tends to suggest that the 'van is running slightly nose down which puts excess load on the front pair. I would suggest some careful measurements to make sure the 'van is running level when hitched up.

There is no requirement for caravans to 'run level' .

The caravan manufacture has certain regulations to comply with when designing their products. One is the standard hitch height when coupled to a saloon car is a nominal 385 +/- 35mm to geometric the centre of the ball. Provided the outfit complies with this measurement it is classed as normal. With permitted a 70mm range on the hitch height, the chances are very few caravans would actually be 'level'.

Prof
Sir WC makes a very valid point on causation of the OP.
What you say doesn't have relevance to his point on causation.
What is the case with a TA is the setting up to ensure the TA is "level" at the point of hitching up..In this regard I am a firm advocate of self levelling suspension particularly as TAs do well with high nose weights.
As you have said before the dynamic loads will change from one axle to another on the move.BUT if you start nose down surely problems will arise?

 

[ProfJohnL]

Hello Dusty,

Changes in caravan attitude will produce different loadings on the axles, We have discussed at some length the issues of climbing kerbs and the effects on weighing TA caravans, and this falls into the same ballpark, but to a lesser degree. It is part of the EU construction and use regulations that sets out the permitted hitch height variations for saloon cars. This is 350 to 420mm, and caravan manufacturers will be very well aware of this and they are required to design their products to accept this range of variation.

Logically, for a caravan to be level, the hitch must be at some specific height., but as the caravan manufacturers must accommodate the vehicle hitch height variations, it follows that every caravan may be towed at any angle the hitch height variation creates. That may include nose down, level and nose up. To put this into perspective it will of course depend on the dimensions of the caravan, but , the +/-35mm at the hitch usually translates to less than +/-2 degrees of tilt.

Unless you have the luxury of adjustable suspension the odds of a caravan actually being 'level' when its hitched are pretty close to zero.for that reason there is no requirement for caravans to be towed 'level'

There is a tradition amongst many caravanners that says you should tow with a nose down attitude, but you know my views on traditions, and as far as I can see there is no technical advantage to nose down or level, and disadvantage in nose up, within the permitted range of itch heights.

Where that range maybe exceeded is with commercial vehicles and some 4x4's that are not subject to the hitch height regulation. If someone was using a dropper plate that might lower the hitch enough to start to produce a marked difference in caravan axle loading, but I suspect you would end up with grounding tow tow hitch quite frequently

My gut feeling about the OP's problem is its more likely to be faulty or damaged tyres, rather than towing attitude.

 

[Gafferbill]

...........I would also be looking at under inflation of the tyres as a possible cause.

Twin axle caravans tend to be fitted with lower specification tyres that run at lower pressures due to there being 4 tyres carrying the weight. This makes them more vulnerable to the loss of relatively small amounts of pressure and can in extreme circumstances lead to tyres being unseated during sharp turns if the pressure falls too low.
Low pressures will cause a heat build up when towing at speed and this could cause failure.

 

[ProfJohnL]

I totally agree with the sentiment of Gaffers comment, but there would have to be a serious loss of pressure to cause a tyre to become unseated, in normal towing, and the types of turns that might cause intensity of tyre scrub rarely occur at high speed or in normal towing, only low speed maneuvering.

 

[MichaelE]

I just replaced all 4 tyres on my 2012 van, i noticed 1 tyre had cracking in the side wall , all the tyres were marked 2/11 so for piece of mind i replaced all 4 these were marked 0815 so hot off the mould !! At £32 a tyre plus fitting its a small price to pay. One thing i did notice is none of the wheels were balenced and Elddis made a big thing about having balenced wheels!! Maybe they forgot to do mine?

 

[WoodlandsCamper]

..........all 4 these were marked 0815 so hot off the mould !! ......

They have probably cooled down a little bit, '0815' is week 8, 2015 and NOT August 2015.

 

[MichaelE]

..........all 4 these were marked 0815 so hot off the mould !! ......

They have probably cooled down a little bit, '0815' is week 8, 2015 and NOT August 2015.

Learn a new thing every day

 

[M5WJF]

As regards tyre pressures, I always look at the load index on the tyre wall for the original tyres fitted as original equipment, together with the manufacturers recommended pressures.

Frequently new tyres that are fitted will have a different load index, and may require a change in the pressure to compensate.

In addition, although a car/caravan/trailer manufacturer might indicate a maximum pressure for OEM tyres under load, if you actually weigh the car at a weigh bridge and make the right calculations, you might find that a lower pressure than the recommended one is more appropriate.