Superb front brake binding

[Scott78]

Hi

I'm having an on going problem with the brakes on my superb. Pads and discs were all replaced 6 months ago, then cleaned up again in November. Two weeks ago the front caliper, drivers side started binding, mpg dropped and the disc was very hot. Garage had a look at it, pushed back the piston and thought it would be ok. Problem still there, so the garage fitted a new caliper last week. Was ok for a day then problem back again, very hot disc. The other three brakes seem fine. Does this suggest a more serious brake problem such as the master cylinder?

 

The car is a 2011 4x4, 85,000 miles.

 

Any help appreciated.

Thanks

Scott

[bigjohn]

Just in case - could it be wheel bearing? If they fail they can generate a huge amount of heat and drag

 

If it's the brakes coming back after a week - sounds like caliper not sliding correctly (Depending on caliper - check slider pins)

 

[EDIT] - how old is the car ? - Could also be flexible hoses collapsing if getting on a bit (blocks fluid return) - If it is change them ALL

 Also - if brake fluid not regularly changed could be the ABS unit

Edited 25 February, 2017 by bigjohn

[Scott78]

Ok, cheers John. I'll ask the garage to check the hoses, don't think it's a wheel bearing as that would be noisy too?

[Racataian]

I bet on the ABS

[peterposh]

The calipers slide on pins /rods to ensure they say central with wear, these can stick with rust and dirt

[26DIPP]

Is the boot damaged with a consequent water ingress and rust on the piston. I had this on a previous car. A new caliper sorted the problem.

[chimaera]

It happened me on a previous car that the boot on one of the slide pins had popped off and allowed the pin to corrode and stick. Once I'd freed it up, cleaned it with emery paper, covered it in copper grease and popped the boot back on it worked perfectly.

 

Get the ABS controller scanned for faults too though.

[Scott78]

Thanks for the advice guys. Update is that the garage checked the car this week, took it for a long test drive, and couldn't find any problems at all. I still think the disc on the new caliper is hotter than the rest, but the car is driving better- pulling smoothly. Maybe it's just the new caliper bedding in? 

Cheers

[gianthotdog]

Did the binding caliper not damage the disc? 

 

Were there any hot spots on the disc? If so then you have basically got a warped disc. Some people say warping discs is a myth however I use the term loosely for a "damaged disc". The excessive heating with the binding caliper will have subjected the disc to temperatures beyond its limit.  

 

I think a new set of discs and pads along with the new caliper may have been best practice. 

[Tilt]

2 hours ago, gianthotdog said:

Did the binding caliper not damage the disc? 

 

Were there any hot spots on the disc? If so then you have basically got a warped disc. Some people say warping discs is a myth however I use the term loosely for a "damaged disc". The excessive heating with the binding caliper will have subjected the disc to temperatures beyond its limit.  

 

I think a new set of discs and pads along with the new caliper may have been best practice. 

 

If he had a warped disc he would feel it when braking.

[gianthotdog]

A binding caliper and hot disc is a recipe for a warped disc.

 

cant see how a binding caliper won't damage the disc. Due to the problem not going after a new caliper I would seriously look for damage to the disc. 

 

It starts with a very minimal wheel wobble and over time develops into a very bad wobble. 

 

Checking the discs is easy with your eyes through the rim, or Jack it up and have the wheel off and compare it to the other side visually.

 

you could swap the discs over. If the problem appears on the other side you know it is prob a warped disc??

 

the OP ended with "any help appreciated".

im trying to help as I've had this problem myself.

[Tilt]

15 hours ago, gianthotdog said:

A binding caliper and hot disc is a recipe for a warped disc.

cant see how a binding caliper won't damage the disc. Due to the problem not going after a new caliper I would seriously look for damage to the disc. 

It starts with a very minimal wheel wobble and over time develops into a very bad wobble. 

Checking the discs is easy with your eyes through the rim, or Jack it up and have the wheel off and compare it to the other side visually.

you could swap the discs over. If the problem appears on the other side you know it is prob a warped disc??

the OP ended with "any help appreciated".

im trying to help as I've had this problem myself.

He may well have a warped disc. I didn't refute anything you said.

 

However, I have also had problems with brakes binding on my Skoda, and noticed one in particular getting very hot but it did not damage the disc. I have replaced both front calipers and one rear so far at different times but with no issues with the discs.

 

I have had an issue with steering wheel wobble (only felt whilst braking, as mentioned) on another car and this was sorted by fitting new discs (and pads) only.

 

And sorry, but there is no way you can tell a disc is warped just by looking at it, even if it was off the car.

[gianthotdog]

44 minutes ago, Tilt said:

He may well have a warped disc. I didn't refute anything you said.

 

However, I have also had problems with brakes binding on my Skoda, and noticed one in particular getting very hot but it did not damage the disc. I have replaced both front calipers and one rear so far at different times but with no issues with the discs.

 

I have had an issue with steering wheel wobble (only felt whilst braking, as mentioned) on another car and this was sorted by fitting new discs (and pads) only.

 

And sorry, but there is no way you can tell a disc is warped just by looking at it, even if it was off the car.

The only way you can tell if a disk is warped is by measuring it's run out I think. I'm not a technician I must say.

 

however visual inspection is a good place to start. If the disc is a blueish colour or has spots on then a high chance it's time to change. The tolerances on the disc/pad surface is so tight that the slightest anomaly will create so much friction and heat.

 

its all time and money vs just putting new on. New are only approx £90 a pair? 

 

I I would defo try swapping the discs over? Good process of elimination?

 

this is a photo of my warped disc. Pretty obvious when you look at it?

 

The inside of the disc is almost trying to get out that is what causes the spots. These are actually slightly raised on the disc, hence the wobble.

 

Edited 16 March, 2017 by gianthotdog
Spelling error

[Tilt]

7 hours ago, gianthotdog said:

The only easy way you can tell if a disk is warped is by measuring it's run out I think if your steering wheel wobbles when braking.

 

 

 

 

As stated earlier.

 

On ‎15‎/‎03‎/‎2017 at 18:40, Tilt said:

 

If he had a warped disc he would feel it when braking.

 

The inside of the disc is almost trying to get out?.................Out of what?

[gianthotdog]

14 minutes ago, Tilt said:

 

As stated earlier.

 

 

The inside of the disc is almost trying to get out?.................Out of what?

I love being quoted and corrected in red. It's like being at school.

 

what do you think to the picture of my disc Tilt? Do you think it could be helpful to the OP?

 

what do you think to the suggestion of Scott78 swapping his discs over to see if the problem follows the disc or not?

 

when I say "it's almost like the inside of the disc is trying to get out" I mean the heat spots look like the internal vents have basically cooked and are trying to burst out from within the disc itself.

 

 

 

 

 

 

 

[Tilt]

The op has (had, as it's probably sorted by now) a problem with his front brake, and if he had a warped disc as you suggest

 

HE WOULD FEEL IT WHILST BRAKING....................HIS STEERING WHEEL WOULD WOBBLE............SIMPLES.

 

you even said it starts with a very minimal wheel wobble, so why you had to question my post at all bewilders me, as it is obvious if you read my post that I did not dispute the possibility of a warped disc, just that he would know (and would have probably mentioned it also) if he had steering wheel wobble.

 

I was not correcting you in red, or it was not my intention either way.

I do not see how your picture can help the op, but if you ask scott maybe he will tell you wether it does or not.

I think suggesting swapping his discs over is a waste of time, as you ask, because all he has to do is feel if his steering wheel wobbles whilst braking.

 

You mention the photo of your warped disc, and state it is pretty obvious when you look at it, yet your first line in the same post states that the only way you can tell if a disc is warped is by measuring it's run out, you think.

[bigjohn]

In my experience unless really bad and overheated it's difficult to spot a warped disc

 

In the past if you had warped discs if not too old it was beneficial to get them skimmed as the overheating that caused the warping also effectively heat treated the metal. Once skimmed they rarely warped again. Probably different with modern ventilated discs. On older Fords - I almost expected this

[peterposh]

If you had a sticking caliper and had it changed , did they change the possibly warped disk as well at the same time?

Edited 18 March, 2017 by peterposh

[Scott78]

Thanks for the advice guys. Useful points made regards the disc possibly being warped by the caliper, I hadn't thought of that. I'm being guided by the garage who confirm that there's no problem. I'll keep a look out for any steering wheel wobble. Although the discs are getting hot, I'm getting 50+mpg on the trip computer out of town, so maybe it is ok.

Cheers

Scott

Cheers