Problems With Xr6t Brakes

[Mondie]

Good result XRTank.

Did you get offered any reason as to why the discs warped in the first place and why it wont happen again?

[XRTank]

Did you get offered any reason as to why the discs warped in the first place and why it wont happen again?

Only, "Gee, that's a bit strange. Normally we get these type of problems with AUs that have travelled 40,000+k's".

It will be interesting to see what other members experience. OwnaXR6T has stated the same problem. I suggest that he too get his replaced.

[physh]

Fade is normally when the brakes get too hot, and either

a ) gas builds up between pad and rotor, meaning less friction = less braking power (x-drilled / slotted rotors help reduce this, which the standard falcon brakes are not); and/or

b ) brake fluid gets beyond operating temperature, boils, and in doing so converts some to gas (which can compress - remember Auto Tech 101? brakes are generally hydraulic in nature, with force assistance from the engine in some way, usually vacuum) meaning less pressure = less hydraulic force behind pistons of calipers = less grabbing/braking power, ie fade.

Probably a few other reasons too, but they're the main ones that I know of.

What I DO know is that the feeling of your foot hitting the floor on the brake pedal and not slowing down at all is a "bad thing"...

Shuddering usually happens when people either

1. ride brakes for a long time / use hard, then stop dead with the brakes still hot. (Anyone ever heard that horrid little "tink" of a rotor cracking???

2. Drive for a while on dry roads etc getting the brakes warm, then going through a puddle (or washing car with hot brakes) - anyone heard of thermal shock?

Metal expands when heating up, and contracts when cooling down. (well duh, physh...)

Metal doesn't like cooling down quickly, and when cooling - one area of the metal can cool down at different speeds to other areas - meaning potential for uneven cooling. This stresses the metal, potentially making it warp under the stress...

Uninvited water on hot brakes is a usually quick way to cause rapid contraction and pretty soon afterwards you'll be fighting the steering wheel under heavy braking... :/

Now I've lectured everyone on thermo dynamics of metals and basic brake theory (badly I might add), I'm gonna go back to skulking for a while... B)

Cheers

oh - and another thing I heard today is that on new Mercedes, they have the brake rotors + pads set up so that they wear out at the same rate... ie, after 25,000km they do a full brake replacement of rotors + pads.

They don't machine em...

Crazy!!!

[AMoffat]

The last bit about how short a life brake discs (rotors) have is well made.

To achieve the sort of braking dynamics that are possible on modern cars - the price is that you need to replace the rotors far more often, along with the pads.

That's just the way is it. The premium brakes are the same. But force applied to rotors, and the dispersion of heat is better on the premium set up. It doesn't mean however, that the rotors will last longer.

Abuse the brakes, drive it hard. Pay the price.

[forrestd]

XRTank,

on your trip to tassie,

did you cross any weirs or other water crossings?

(perhaps extremely hot to very cold isnt a good thing)

btw, when are we going fishing next?

[Guest woosh]

is their good aftermarket brakes besides brembos?

[Anthony-XR6T]

Just came back from the NSW south coast with shuddering brakes. I am pissed off that this has happened with 4000km on the clock. I will be booking it in to service this week and I will see what they have to say about it.

Another problem I have is the window control module on the drivers door has popped out, the locking clip is broken and will not go back in. Intermittently when I unlock the car the drivers windows goes down- this may be related to the module?

[Turbo6man]

Premium brakes suffer from the shudder too. And it seems to be common that rotors and pads wear out much more quickly with today's "environmentally friendly" materials. I've seen it reported that rotors will only last two or sometimes three pad changes - not good for the hip pocket. This is the cost for protecting the environment - no asbestos etc.

[Guest harasn]

Anyway, feeling bit happier about the whole issue, but now wish I had gone with the premiums! BRAKE FADING IS STILL THERE!

if your finding brake fade with the standard system then I suggest your driving way to hard on the brakes, you need to option in the brembos. We can stop from 200kms and no fade. Where are you driving to get brake fade and how fast are you going before and after your applying the brakes, on a race track?

don't get me wrong they need to fix the brake shudder but I think your case is from over use rather than normal conditions. You must be enjoying the power!!!

[XRTank]

did you cross any weirs or other water crossings?

Definitely not, however, some of the roads were quite twisty coming down a few passes. I had some fun on these roads but I wouldn't say that I drove the car hard. I try and stay off the brakes whenever (sensibly) possible.

The fading that I reported maybe something else. What I experience is the need to apply more pressure to the brake pedal than when I originally first had the car. The pads feel less 'meatier' (maybe this is normal?). It still feels safer than my old Pulsar.