When you work in a workshop this is a term we really get to hear. This does not mean that this is not crucial. This means this does not happen as frequent as any other failing components.
Do you know what it means?
Or do you just guess?
This is an extremely dangerous thing to happen in general and even more so when you have your family in the car and you are in a high traffic area.
Lets start with the basics.
What is brake binding?
Once the applied strain is ransomed, the brake pad has to move away from the disc to dislodge the braking force. But if it does not move, then binding will be the cause. The oversized brake pad is the main cause of brake binding because the additional size does not allow the pad to move freely in the brake calliper.
What does it mean when your brakes are binding?
Excessive Brake Component Rust
When rust builds up on the carrier and pads, it causes them bind. Basically the pads are wedged into the rotor and they can’t move back. As the pad is making contact with the rotor all the time, heat builds expanding the metal and the problem snowballs
Is brake binding dangerous?
If you have a stuck calliper, the brake pad will not completely disengage from the surface of the brake rotor. This means you will be driving with the brakes applied slightly all of the time. Driving with a stuck calliper can create stress on the transmission, causing it to fail earlier
How do I know my brakes are binding?
Jack the wheel up. On an undriven wheel simply spin it and it will be obvious if the pads are binding as there will be a noise and resistance to turning. On a driven wheel it isn’t so easy. Compare the thickness of pads on either side of the disc and each wheel.
Can a brake unseize itself?
In most cases, a seized brake calliper manifests itself as reduced braking power. Usually, when a brake calliper seizes, the brake pad on the side of the calliper piston will wear excessively. Eventually, the brake pad will wear down so much that it can affect the brake disc which will get damaged
What does a seized calliper sound like?
Squealing or metallic rubbing noise.
If a brake calliper is sticking or freezing up, noises may be heard from the area of the damaged part. Unlike the noises related to worn brake pads (which occur when the brake pedal is pressed), this symptom is likely to be heard when the brakes are not being used
Proper brake maintenance begins with regular inspection. Better to find problems before they find you.
So what causes the brakes to bind? The most common reasons brakes bind include:
· Binding calliper pins
· Calliper piston frozen
· Excessive brake component corrosion
· Parking brake cable binding (rear brakes)
· Damaged brake shoes (rear brakes)
· Overfull brake fluid
· Bad brake hose
Binding brakes is common and it’s usually related to corrosion, but as you can see from the above list, they can bind for a ton of other reasons too.
We’ll deal with each possibility in order of how common it is, make sense? But first let’s do a basic brake check.
Warning, some cars are fitted with dynamic braking systems, these systems can be dangerous to work on without disabling them first. Check if your car is fitted with a brake assist system.
Basic Brake Check
Check your dashboard for the ABS light, it should come on with the ignition switch and go out when the engine is running. If the ABS light remains on, you’ll need to scan the controller for fault codes.
The first inspection is a visual of the wheels. Very often the wheel that’s binding will have a lot of extra brake dust on the wheel rims.
If the brake fluid level is over full, you may have found your problem. Brake fluid expands as it heats and will push the calliper pistons out.
If the fluid is very low, it’s a sign the brake pads or shoes are worn or you have a fluid leak. A leak is less likely as your brake pedal would be very noticeably soft.
Most cars and trucks today have wide spoked wheels, which is great for inspecting brake pads and callipers. It’s not fool proof as the inboard brake pad will be hidden and some many vehicles are prone to excessive inboard pad wear.
So if the outer pad is low, you can bet the inner is very close to steel on steel.
Before working on your cars braking system, be sure it’s safe to do so. Some modern cars will be equipped with auto braking meaning they have a pre-charge. It’s a store of braking energy used for emergency stops. This system needs to be depressurised before opening brake lines or removing callipers.
Integral ABS systems likewise hold a charge, you’ll recognise this type system as the ABS pump accumulator and master cylinder are all in one.
Some modern cars will have an electronic parking brake, this system will need to be placed in service mode before attempting a repair.
Some cars will run drum brakes on the rear but most will have rotors and callipers all round. Rear calliper pistons will likely be screw type, that means you can’t treat them like the front, they need to be screwed and pressed simultaneously. A special brake calliper tool makes life a lot easier.
Binding Floating Calliper Pins
Floating callipers are the most common type brake hardware set up. The calliper is free to move over and back on smooth lubricated pins as the brake pedal is applied.
Trouble starts when one or both of the pins get dry, the calliper then moves across the pins unevenly, which can cause the brake calliper to stick on.
Calliper Piston Frozen
Excessive Brake Component Rust
Corrosion is common, there’s no escaping it, that’s why regular brake inspections will help you prevent major brake problems.
When rust builds up on the carrier and pads, it causes them bind. Basically the pads are wedged into the rotor and they can’t move back.
As the pad is making contact with the rotor all the time, heat builds expanding the metal and the problem snowballs.
If the problem is ignored, it can cause rotor, wheel bearing, ABS sensor and ball joints to fail.
Repairing brake carrier corrosion is an easy fix, you’ll need a wire brush, sandpaper, Copper, Moly or Graphite dry grease, and a new set of brake pads.
Rotor corrosion can cause the brakes to stick and sticking brakes causes heat which as you know compounds the problem.
Heavily corroded rotors happens more commonly to cars that don’t drive very far, or very often or brakes that are only lightly applied. Under normal driving conditions, braking cleans the rotors and prevents pitting and corrosion.
Parking Brake Binding
All cars run the parking brake to just the rear wheels and as you know, some vehicles have callipers at the rear and others will have drum brakes.
The parking brake on most cars are still operated by pulling a lever which pulls a cable which applies the rear brakes.
The park brake cables often corrode internally, which can cause them to partially stick in the on position. The fix here is to replace the cables.
A park brake cable that’s been adjusted too tightly, will cause the rear brakes to bind. This usually only happens when the brakes warm up.
The fix is to back off the park brake adjuster, usually found at the hand brake lever.
Callipers rear brakes, commonly have a cable operated lever. The lever on the calliper will often stick either in the on or off position. This happens a lot with car owners that don’t use their parking very often.
Damaged Rear Brake Shoes
Less expensive cars are fitted with drum brakes, they’re pretty dependable but have many moving parts.
Clips, springs, and shoe linings can come loose and get caught in the drum, causing the hub to bind or lock.
A leaking wheel cylinder will cause binding too. The fix here is a complete rear brake job.
With each and every car that enters our workshop we make sure to do a full inspection of the car, with every inspection we give our customers a detailed quotation.
We know how important it is for each and every customer to make it home each and every time.
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