Warped Discs.

Chris100

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Hey all,

Can anyone advise what causes warped discs? My car is only a few years old, and has less than 24k on it.

From the symptoms it certainly feels like warped discs, however with the age and mileage I can’t understand how this would be the case.

Also, is it safe to still drive the car? Or should I refrain from driving it until these are sorted.

Cheers,
Chris
 

Todd

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Another cause is washing the car when the discs are still hot. The cold water can cause the discs to warp!
 

IL

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The Boxster?

My Cayman Discs rusted on the inside surface, wasn't visible with dust plate until the disc was removed.

Too much wafty / city driving at the time, caused a wrap like symptom.
 

Chris100

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Chris100
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The Boxster?

My Cayman Discs rusted on the inside surface, wasn't visible with dust plate until the disc was removed.

Too much wafty / city driving at the time, caused a wrap like symptom.

Yep, it’s the Boxster.

I had it down at Porsche for a brief inspection, they didn’t take anything off the car.

Its booked in next month, but thinking about it after I left I wasn’t really happy with their explanation of why this May of happened and there was no acceptance that it could be a warranty covered issues, and they didn’t say it wasn’t safe to drive the car.
 

IL

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Yep, it’s the Boxster.

I had it down at Porsche for a brief inspection, they didn’t take anything off the car.

Its booked in next month, but thinking about it after I left I wasn’t really happy with their explanation of why this May of happened and there was no acceptance that it could be a warranty covered issues, and they didn’t say it wasn’t safe to drive the car.

Anything Brake Related such as Rust, Wear, Warp etc will not be covered by Warranty, it's wear and Tear.
 

Chris100

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Chris100
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Wear is fine, I accept that. But surely warped discs is not normal wear and tear, brake discs with only 23k on the car should not be warped or they should at least be able to give me a sensible explanation as to why they are warped.
 

IL

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Wear is fine, I accept that. But surely warped discs is not normal wear and tear, brake discs with only 23k on the car should not be warped or they should at least be able to give me a sensible explanation as to why they are warped.

Warped discs are usually due to over heating, and therefore down to how the car has been driven

My Cayman discs had 1/3rd of the inner circumference of the disc surface covered in deep rust at 30k - both fronts where replaced, car was perfect after.
 

Chris100

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Chris100
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Warped discs are usually due to over heating, and therefore down to how the car has been driven

My Cayman discs had 1/3rd of the inner circumference of the disc surface covered in deep rust at 30k - both fronts where replaced, car was perfect after.

Only me driving the car, I don’t drive it differently to any other car I’ve owned. I have never had to replace discs on any other car I’ve owned, I usually don’t keep them for more than 3 years and they are bought new, so usually don’t get above 30k miles.

Porsche brake discs must be ***** if they can’t last more than 25k miles with some occasional quick driving, surely the brakes on a sports car should be designed for that.
 
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Coog

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Can be any multitude of things causing them to warp. Keeping your foot on the pedal at the end of a motorway slip road or after any hard stop, rust, contamination, hit with a hose / puddle when they were hot, crap discs / pads, worn bushes, mis-fitted parts, etc. Pick one out of that list. That's probably what caused it.
 

Ian A

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Agreed with the guy's points above, it wouldn't be fair to blame Porsche or the disc quality given just how many factors could be at play. Sometimes can be plain old bad luck.

Sticking caliper could be heating the bejesus out of it the disc too, if you notice higher than normal brake dust deposits on a wheel. That is one would be worth enquiring with the dealer for a fresh car with low miles.

Otherwise could just be 1 of those things unfortunately.
 

KevM

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I think you'd be going really really well to warp modern Porsche brakes.

As IL has said, the issue is normally due to under-use and an uneven build up on the inner surface of the disc.
 

Tufty

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Check for rust or dirt on the wheel hub surface
WHY?
Rust or dirt causes poor contact between the disc and hub.
THE SOLUTION: Dismantle the disc and clean both surfaces to remove rust and other pollutants.

Check whether the hub contact surface has been distorted by excessive tightening torque
WHY?
Using overly severe tightening torque on the positioning screw leads to vibrations throughout brake application.
THE SOLUTION: Replace the discs, avoiding excessive tightening torque.

Check for distortion of the hub itself
WHY?
Although rare, it’s possible for hubs to warp. Bolting a disc to a warped hub will always result in brake vibration. The same will happen if any rust from the hub surface is not removed before fitting the disc.
THE SOLUTION: After fitting a disc, always check for disc run-out using a dial gauge. If the run-out is out of tolerance, re-fit the disc in an alternative position until the run-out is within tolerance. If run-out still remains out of tolerance, hub maintenance is required.
 

stevieturbo

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Wear is fine, I accept that. But surely warped discs is not normal wear and tear, brake discs with only 23k on the car should not be warped or they should at least be able to give me a sensible explanation as to why they are warped.

If they are warped, it is very easy to prove by measuring runout with a dial gauge.

Of course you could easily cause harm to discs to warp them in a few hundred miles, so 23k doesn't mean much. They won't know how or where it has been driven.

But if they did not measure or inspect anything....how can they create any explanation for whatever it is they're explaining ?

Did they drive the car ? Do they agree there is anything wrong with them ? Can they feel whatever it is you're saying is there ? Or do they deny all ?
 

Chris100

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Chris100
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If they are warped, it is very easy to prove by measuring runout with a dial gauge.

Of course you could easily cause harm to discs to warp them in a few hundred miles, so 23k doesn't mean much. They won't know how or where it has been driven.

But if they did not measure or inspect anything....how can they create any explanation for whatever it is they're explaining ?

Did they drive the car ? Do they agree there is anything wrong with them ? Can they feel whatever it is you're saying is there ? Or do they deny all ?

They drove the car, did a quick visual inspection (nothing was remove). Following this they said discs are warped and need replaced, nothing much else said. They haven’t been replaced yet, going in next month for this.
 

Martyn

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Yep, credit where it’s due. Can’t fault them on this occasion, Porsche Belfast really did go that extra mile with Porsche GB to get the warranty to cover them.

Porsche Belfast seem to get bad mouthed regularly. I have always found their pricing, going the extra mile to get a job done second to none.

You pay for a premium service, and they provide.

Good to hear you had the same experience Chris.
 

zafturbo

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7,433
Porsche Belfast seem to get bad mouthed regularly. I have always found their pricing, going the extra mile to get a job done second to none.

You pay for a premium service, and they provide.

Good to hear you had the same experience Chris.
Any idea on the hourly service charge from Porsche .?
 
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