560 brakes come on while driving

jordanlott

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Hi The brakes come on by them self mostly when Im driving longer distances.
I have had new disks ,brakefluid and pads fitted which helped a lot but not totally. Now six months later it is starting again.
Any ideas
Jordan

The great 5.6 liter costs enough in:( fuel without driving with the brakes on
 

brandwooddixon

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Do you mean that they come on all of a sudden or gradually and start to "bind".

Which pads wear the most? Quite possibly the caliper pistons need freeing up.

Alternatively I suppose that you could have poor adjustment on the master cylinder?

Does your car have BAS?
 
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jordanlott

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Do you mean that they come on all of a sudden or gradually and start to "bind".

Which pads wear the most? Quite possibly the caliper pistons need freeing up.

Alternatively I suppose that you could have poor adjustment on the master cylinder?

Does your car have BAS?
Hi Thanks for quick reply
Answer is slowly start to bind first High pitched squealing some times stopped by tapping pedal but I can still feel breaking.
It was so bad before the new disks pads fluid that the car would actually come to a full stop after coasting ie breaks part on.
ABS STP lights do come on by themselves sometimes but go out immeadialy on restart.
Jordan
 
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jordanlott

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Do you mean that they come on all of a sudden or gradually and start to "bind".

Which pads wear the most? Quite possibly the caliper pistons need freeing up.

Alternatively I suppose that you could have poor adjustment on the master cylinder?

Does your car have BAS?
Hi Yes ABS etc.
How does one adjust a Mastercylinder
Jordan Thanks
 

brandwooddixon

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I would look at sticking caliper pistons first.

You'll need to remove the cailper, clean it up and fit new seals. That'll requrie whats known as a caliper repair kit.

Give the caliper a good clean using a wire brush and ensure that the sliding surfaces for the pads are clean, allowing easy movement of the pads, before disassembly.

I've had old cars in the past where the exposed section of piston rusts and wont retract. This can be cleaned off with careful use of very fine wet and dry. Just need to ensure that all parts are clean and dry before reassembly (using some brake fluid as lubricant).
 

television

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On the last car with this problem it was found to be the hoses had collapsed inside, stopping the natural action of the pistons to retract, the brakes get hot and the expansion starts of the pads and disc and they finally bind up .
 

Creme Eds

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Agree with the above, you most likely have one or more binding calipers,
especially on a car that age. To test:

1) Bring it to a garage and put it on their brake tester (easy!)
2) Go for a longish drive, then touch the disks. If you get burnt, you've found the wheel with the binding caliper (painful)
3) Jack up the car and whizz the wheels around by hand fast as you can, see how long they run on after you let go. (bit of a black art but you may see one wheel significantly stiffer than the rest. Or then you may have 4 binding calipers which is no fun)

Then you need to fix it. The calipers will most likely need to be completely dismantled which is a messy job not helped as brake fluid is evil. Having taken them apart and cleaned them until they shine, you may need expensive new seals and pistons to rebuild them and also face the prospect of the rusty bleed nipple snapping off. So, get remaunufactured calipers if they are cheap enough/available.

c.
 
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