# cracked tyre walls and overheated brakes



## kevanna1959 (Apr 5, 2010)

can anyone give us advice, we have a 56 motorhome and have noticed there are small cracks on the tyre walls. we visited several tyre specialists who have said they are nothing to worry about, but we would welcome any advice. then when giong down a steep mountain with lots of bends in germany as we got to the bottom our breaks failed. we have been advised we can get drilled and grilled disc any advice welcome thanks


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## Sprinta (Sep 15, 2010)

check the side walls of the tyres and look for a 4 digit code number eg 2204 on there. This is the date code to show when the tyre was actually made, the example would be 22nd week of 2004.

From the date you can determine how near to renewal they are getting, 5 years old and it's been suggested they should be renewed. Certainly your insurance company would question their age if you had an accident and may decline a payout based on "too old tyres"

I wonder why your brakes failed? what condition are your discs and pads in? Boiled the fluid maybe? There's a few variables that need answering before simply jumping to an upgrade in discs required. 

I always renew my brake fluids as a matter of course at 4 years old, yearly on my bikes, as the fluid degrades over time as it's hygroscopic and absorbs water. I bet not many people here have it done as a regular service.


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## BillCreer (Jan 23, 2010)

Hi,

re the brakes. 
I'd check when the fluid was last changed as water is held in suspension in the fluid, over time, which then boils when the brakes get very hot and unfortunately the water vapour created is compressible rendering your brakes inop.
If you don't come down mountain passes on the gears then most heavily laden cars and vans will have faded out of brakes by the bottom.
I burned the front pads of a very heavily Citroen BX when I was only half way down the Gross Glockner pass. The good thing about that was the brakes still worked because the fluid was ok.


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## Techno100 (May 8, 2010)

Re brakes.
Could just be driving style? try use as much engine braking as possible and keep the speed as low as 3rd gear will let you go, just feathering the brakes for bends


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## TR5 (Jun 6, 2007)

Ventilated discs are made for a lot of vehicles, so you could do a search on the internet for your particular base vehicle make/type.

They will help to cool the brakes when heavily used. Don't forget on long decents that you can reduce using the brakes somewhat by selecting the lowest gear possible for your speed, take it slow, and let the engine 'brake' your vehicle as much as possible.

If this occasion is just a one-off, then I would not bother paying for ventilated discs, but if you regularly use these type of roads, this will certainly help. If you have an auto box, selecting and holding a lower gear will help also.

EBC make good brake pads, and if they supply 'greenstuff' pads for your vehicle, not only do they improve the braking, but they also emit less carbon dust onto your wheels. Certainly a worthwhile choice if you live/use in a hilly clime regularly.

Oh, and don't forget to check the age of your brake fluid.


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## SpeedyDux (Jul 13, 2007)

I get my garage to change the brake fluid every 2 years to maintain a high boiling point. VW recommend this. Over time, brake fluid absorbs moisture and that lowers its boiling point. If the fluid boils you are in big trouble. 

I don't think you can avoid heating up the disks and pads on a long descent. I read some advice that (as well as using a lower gear) you should not keep pressing on the brake pedal continuously. Slow right down where it is safe to do so, then lift off the brakes for a few seconds to allow the disks and pads to cool a bit. Then re-apply the brakes. Lifting off sometimes takes a bit of courage. If you keep doing that then there should be less risk of overheating the brakes and boiling the fluid. If you feel the brakes are getting too hot and spongy then lifting off can help them recover.

Loading the MH up to its maximum payload / MAM will also require you to lose more potential or kinetic energy all of which must turn into heat through the brakes when you descend or stop. Some of that energy can also be dissipated by using the engine as an air pump, when you are engine braking in a low gear. That helps a lot but I am not a big fan of engine braking (unless absolutely necessary) because on the whole new brake pads are much much cheaper than a new gearbox so I would prefer to wear out the pads. 

I used to fit harder competition brake pads to my rally car. They were fantastic and resisted fade beautifully. The drawback was that when cold they did not work at all and the car couldn't stop at traffic lights which was slightly embarrassing. 

You could be pushing the MH brake system right to its design limits if you carry the maximum payload and whizz up and down mountain roads. Also, it is exceptional for converters to upgrade the vehicle brakes with bigger disks and calipers, as well as the suspension and possibly tyres when re-plating the chassis to a higher MAM. If you upgrade your MAM for more payload you should be aware that the brakes will have more energy to dissipate but they are still the same brakes as before.


SD


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## spatz1 (May 19, 2011)

kevanna1959 said:


> can anyone give us advice, we have a 56 motorhome and have noticed there are small cracks on the tyre walls. we visited several tyre specialists who have said they are nothing to worry about, but we would welcome any advice. then when giong down a steep mountain with lots of bends in germany as we got to the bottom our breaks failed. we have been advised we can get drilled and grilled disc any advice welcome thanks


probably overheated and failed and best remembered your motorhome is like a "van" carrying a full payload ... Drilled and grooved wont make a differance bar lots of noise and i doubt you can source a pad that will improve things enough to prevent overheating in those conditions....
My car has yellowstuff pads (aclaimed best ) and even on the staffordshire moorelands i can get brake fade whenever i want and have to moderate my driving style accordingly...


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## karlb (Feb 22, 2009)

Sprinta said:


> check the side walls of the tyres and look for a 4 digit code number eg 2204 on there. This is the date code to show when the tyre was actually made, the example would be 22nd week of 2004.
> 
> From the date you can determine how near to renewal they are getting, 5 years old and it's been suggested they should be renewed. Certainly your insurance company would question their age if you had an accident and may decline a payout based on "too old tyres"
> 
> ...


has anybody got anylinks regarding insurance companys asking questions about the age of tyres?
why would they? 
new tyres fail what then?


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## Glandwr (Jun 12, 2006)

Sprinta said:


> Certainly your insurance company would question their age if you had an accident and may decline a payout based on "too old tyres"


Straight up Sprinta?

Dick


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## Chausson (Oct 17, 2006)

Hi
I used to get brake fade on my Chausson 2006 Transit, I spoke to ferodo [spelling] they told me to upgrade the fluid from DOT 4 to DOT 5, they said if that don't work come back to us and we will make you a set of pads that will work, nose end he said. Anyway changed the fluid and it made the world of difference it actually allowed the brakes to stop the van. Oh and I changed my brake fluid every 18 months previous to that.

Ron


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## DTPCHEMICALS (Jul 24, 2006)

Tyres at 5 years old with small cracks.
Personally I would change them.

Little cracks grow, not shrink.

Changed ours on 55 reg with less than 16k miles.


Dave p


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## Sprinta (Sep 15, 2010)

Glandwr said:


> Sprinta said:
> 
> 
> > Certainly your insurance company would question their age if you had an accident and may decline a payout based on "too old tyres"
> ...


insurance companies in this day and age will want any available reason not to payout on a claim. They wanted me to pay my excess even though it was the car behind me crashing into me and pushing me into the one in front - I soon corrected them but I reckon they'd still try it on with others

if they have a situation of perhaps a tyre failing and causing a collision and the tyres were maybe 10 years old and cracked, do you think they won't want to use that as an easy cop out?

read this from Michelin

http://www.michelintruck.com/assets/pdf/bulletins/TB_Service_Life_RV_Tires.pdf


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## peribro (Sep 6, 2009)

You say that you've visited several tyre specialists and they've all had a look and say they are OK. On the basis that the people you have visited are presumably in the business of selling new tyres then I would draw two conclusions - first is that the people you have visited are honest and scrupulous and secondly that your tyres are OK.


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