Tyre Blow Out - your opinions

[alfaspiderman2]

Travelling back from South of France on Saturday, my 5 Series was clearly unhappy as soon as I hit the Autoroute.

Felt tyre related but, given there were no warnings from the OBC and a visual check suggested all was fine, I pressed on. After about 100kms at 85ish, the noise was getting gradually worse. I put it down to some dodgy French diesel causing a misfire but and pressed on. Then the o/s rear tyre blew out and I was forced to stop.

Having regained some composure, I deduced that what must have happened is that the car must have been running on the 'get you home' run flat from the outset but the sensors had failed to tell me.

Does my interpretation sound right? Should I have got a warning from the OBC? Am I likely to have done any damage driving at motorway speeds for 100ish kms?

Edited by alfaspiderman2 on Tuesday 23 September 14:10

[gizlaroc]

The warning system will worn you of any sudden change in pressues while you car is rolling, it will not however warn you if you have had a flat during the night and you then press on the next day.


You should however notice something is up, which by the sounds of things you did, at which point you can check.

It is a very clumsy system imho, we need a proper pressure monitoring system as poeple become reliant on the warning system that will not always warn us, it is actually pretty dangerous.


Use it as an excuse to put some proper tyres on the car. I would buy a ssingle wheel teh same as you have now on your car off ebay, and then keep one of the run flat wheels as your spare.
The perfect get you home spare wheel.

[alfaspiderman2]

thanks

that makes sense in terms of what actually happened

car is a company car so another run flat will inevitably be fitted - once my car is repatriated that is....currently left stricken in compound near Niort

[Roger645]

gizlaroc said:

The warning system will worn you of any sudden change in pressues while you car is rolling, it will not however warn you if you have had a flat during the night and you then press on the next day.


You should however notice something is up, which by the sounds of things you did, at which point you can check.

It is a very clumsy system imho, we need a proper pressure monitoring system as poeple become reliant on the warning system that will not always warn us, it is actually pretty dangerous.


Use it as an excuse to put some proper tyres on the car. I would buy a ssingle wheel teh same as you have now on your car off ebay, and then keep one of the run flat wheels as your spare.
The perfect get you home spare wheel.

What about if the car dropped 10PSI overnight? Would you get a warning

[DSM2]

gizlaroc said:

The warning system will worn you of any sudden change in pressues while you car is rolling, it will not however warn you if you have had a flat during the night and you then press on the next day.


You should however notice something is up, which by the sounds of things you did, at which point you can check.

It is a very clumsy system imho, we need a proper pressure monitoring system as poeple become reliant on the warning system that will not always warn us, it is actually pretty dangerous.


Use it as an excuse to put some proper tyres on the car. I would buy a ssingle wheel teh same as you have now on your car off ebay, and then keep one of the run flat wheels as your spare.
The perfect get you home spare wheel.

Not true I don't think. If there is a substantial difference between the rolling diameters of two tyres on the same axle, the TPMS should warn.

I recently fitted a new set of 4 to my 320d. turned out one of the new tyres was damaged and couldn't be fitted so I had to run overnight on three new and one old, all fully inflated.

The TPMS warning came on every time
I began to move. I even reset the system but it came right back on till I fitted the 4th new tyre.

My guess the system was not properly initialised.

Edited by DSM2 on Wednesday 24th September 09:03

[DSM2]

gizlaroc said:

The warning system will worn you of any sudden change in pressues while you car is rolling, it will not however warn you if you have had a flat during the night and you then press on the next day.


You should however notice something is up, which by the sounds of things you did, at which point you can check.

It is a very clumsy system imho, we need a proper pressure monitoring system as poeple become reliant on the warning system that will not always warn us, it is actually pretty dangerous.


Use it as an excuse to put some proper tyres on the car. I would buy a ssingle wheel teh same as you have now on your car off ebay, and then keep one of the run flat wheels as your spare.
The perfect get you home spare wheel.

Not true I don't think. If there is a substantial difference between the rolling diameters of two tyres on the same axle, the TPMS should warn.

I recently fitted a new set of 4 to my 320d. turned out one of the new tyres was damaged and couldn't be fitted so I had to run overnight on three new and one old, all fully inflated.

The TPMS warning came on every time I began to move. I even reset the system but it came right back on till I fitted the 4th new tyre.

My guess the system was not properly initialised.

Edited by DSM2 on Wednesday 24th September 09:03

[fixedwheelnut]

Often if a tyre gets to the point where it blows out it is because the tyre warning system has been reset with the tyre still flat.
Most of the customers say they had a tyre warning but they LOOKED at the tyres and they all looked ok
"What were the tyre pressures then?"
Answ "Oh I didn't check them because they looked ok"

Not saying that is what happened but a possibility.

[Andrew D]

DSM2 said:

gizlaroc said:

The warning system will worn you of any sudden change in pressues while you car is rolling, it will not however warn you if you have had a flat during the night and you then press on the next day.

Not true I don't think. If there is a substantial difference between the rolling diameters of two tyres on the same axle, the TPMS should warn.

Err... yes and no on both counts. Any sudden decrease in pressure (and thus tyre radius) will set the system off regardless of whether you're driving or not. However, it will let pressures slowly drop, especially if both ends of the axle are doing so at a similar rate. It will also tolerate different radii (to a degree) if they're different when the system is reset.

So you should only rely on the system to tell you if you get a sudden deflation, and check your tyre pressures regularly. That way you'll at least get better tyre life and avoid uneven wear, and possibly avoid any blow out unpleasantness. I check mine every time I wash the car.

Just a note regarding swapping runflats off; I'm sure the OP was glad he had runflats on when the tyre blew. Possibly a quality for which runflats aren't often given credit.

[alfaspiderman2]

fixedwheelnut said:

Often if a tyre gets to the point where it blows out it is because the tyre warning system has been reset with the tyre still flat.
Most of the customers say they had a tyre warning but they LOOKED at the tyres and they all looked ok
"What were the tyre pressures then?"
Answ "Oh I didn't check them because they looked ok"

Not saying that is what happened but a possibility.

Not in this instance. I only activited the warning system after the problem became apparent. I've certainly learned a lesson here though.