Brake pad thickness (minimum new ideal thickness) - Auto Chimps (2023)

The brakes will not work if the brake pads are worn. You can only stop the car with the engine brake and, if necessary, with the emergency brake.

Luckily, you should never get to that point. Regular checks and metal warning caps provide months of warning.

The thickness of the brake pads should be checked if possible. After all, it's an integral part of stopping your car.

In short, the thickness of the brake pads is crucial to keep track of. In this simple guide I explain the minimum, new and optimal thicknesses for brake pads. I've also included a custom chart.

Let's begin!

How do brake pads work?

Brake pads have a metal backing plate with a high friction surface attached to it. Each wheel has two pads, one for the outside and one for the inside. You hit the brakesPachymeter.

When you press the brake pedal, the hydraulic brakefluidpushes the piston (or pistons) in the caliper towards the rotating rotor. Its friction surface presses against the rotating surface of the impeller.

When the surfaces touch, friction slows the rotor. This, in turn, reduces the rotation speed of the wheels and slows down (or stops) the car.

Note that friction causes the brake pads and discs to become very hot, especially under hard braking.

Because of this, you'll see race car rotors glow orange as they approach corners. When they get too hot, you experience what's known as brake fade - when your brakes stop working properly. Many modern rotors are "vented" to counteract this.

How thick should a brake pad be?

A thick brake pad makes all the difference when stopping. The more material there is, the easier it is to absorb anddissipate frictional heat.

On the other hand, if your pads are less thick than recommended, they will overheat. Your car has drastically reduced braking performance.

This is dangerous for you, your passengers and other road users (including pedestrians).

If grossly neglected, the friction material wears out completely. This forces the metal backplate against the face of the rotor.

When this happens, you will hear a terrible screeching sound (much worse than the warning screech). The car will also have trouble stopping.

In this brake pad size chart you will find a clear table that explains what is ideal, what is acceptable and what is dangerous.

What is the ideal thickness of brake pads?

How thick should the brake pads be? Ideally,6mm or more. If it falls below 6mm, the brake pads (in most cases) will no longer function efficiently.

They will be fine for a while; They usually don't need to be replaced. Follow your mechanic's advice.

When the pads reach 3mm, they need to be replaced. Not the legal limit, yes. However, most experienced mechanics agree that this is the minimum safe thickness for brake pads.

What is the legal minimum thickness of brake pads?

Realistically, you should always keep the pads above 3mm.

Islegal minimum thicknessfor the steering axle is 1.6 mm for hydraulic disc brakes and 3.2 mm for air brakes. As always, measure this from the steel backplate to the lowest point of the pad.

This may be the minimum legal requirement, but that doesn't mean you should let your brake pads wear to this point.At 1.6mm, the brakes are dangerously ineffective.

Brake manufacturers will tell you when the pads and rotors need to be replaced. It is best to follow their guidelines.

When should I check the thickness of the brake pads?

You should check the thickness of the brake padsevery 5,000 km or a few times a year. Mechanics should check the brakes at every visit. It is best to ask specific questions to be on the safe side.

In general, you should expect a long service life from brake pads and discs. 40,000 miles (depending on your driving habits and techniques) is a reasonable average.

If you're hearing a high-pitched squeak from your wheels, it's almost certainly your brake pads. This is an indication that they have reached the minimum thickness required by law.

Take your car to a technicianimmediatelyand have the brakes replaced.

It is recommended to replace pads and rotors at the same time.

How is brake pad thickness measured?

Measuring brake pad thickness is a relatively easy task, but usuallyis to take the wheels off. You will need (at least) a jack, axle struts, brake levers, wheel nuts and a torque wrench.

take agauge tool. You need to find the special tool that fits snugly between the pad backing plate and the face of the rotor.

This reading is the thickness of the brake pad.

If you removed the pads, you can use a more genetic method. Mechanics often use aTire tread depth gauge against base plateto measure the cushion thickness. Take measurements in multiple locations.

Retighten the wheel nuts to the correct dimension when changing tires.

Note: It is also possible to measure the thickness of the brake pads without removing the wheels. However, this can be difficult to do with any degree of accuracy. It's almost impossible to measure the outside tread unless you have alloy wheels. You can check the interior by turning the steering wheel as far as it will go and stepping under the vehicle.

Do some brake pads last longer than others?

Not all brake pads are the same. Not true in all cases, but in general you get what you pay for.

Inexpensive brake pads are typically made from cheaper materials that are less effective at dissipating heat energy. The more expensive parts should work much better.

However, be careful with the brand. You don't have to buy the best brand of brakes; Most people can't see them anyway. Instead, focus on the best materials for your brake pads and make sure they are OEM material.

High performance brake pads are not always necessary, especially if you drive a small, light vehicle. However, look for ceramic or metal options for the best stopping power. Ceramic pads are more efficient under load because heat is less of an issue. Still, they're often expensive, and you need to buy quality rotors to go with them. Therefore, metal brakes are the most common choice for everyday drivers.

Organic brake pads are also available. Once made from asbestos (no more!), these options are usually within budget. They're cheap, but they don't last as long or work as well, but they're still nice and will work reasonably well.

How thick are the new brake pads?

New brake pads should be 12 mm thick.If you change the brakes on a rear wheel, the pads can be a bit thinner (8 to 10mm).

If you want to check it yourself, you can measure the thickness of the pads before inserting them into the caliper. A simple ruler or tape measure will do.

You can see these readings in the pad thickness chart above.

Why aren't my new brake pads stopping the car?

For more information on the cost of replacing brakes, see the guide below.

Related:Cost of replacing brake pads and rotors

When replacing the pads (ideally for the rotors) you may find that the car has trouble stopping. This happens when the brake pads "sink" into the brake discs and form a groove where they will soon become lodged.

There shouldn't be any problems with the brake pads.

Mechanics must take the car for a test drive in an empty secure parking lot (or similar) to accommodate them. You step on the brakes multiple times, forcing the pads to dig into the rotor.

After returning the car, if you still feel it is having trouble stopping, take it to a safe but secluded location. Do it yourself a few times.

Braking performance should return to normal shortly.

The problem is still there? The brakes may need to be bled or the calipers replaced.

Diploma

It is always important that your brake pads are in good condition. These are not parts you would normally look at, so examining them specifically is imperative.

If they are less than 6 mm, you should replace them with new ones. Never let them fall below 3mm.

Of course, the new pads should be 12mm in size and last a few years. You may need to replace them sooner if you tend to brake too hard most of the time.

The best way to ensure your brake pads work well and last a long time is to ride and brake gently. Only fully depress the pedal in an emergency.

To take a brake pad measurement, obtain caliper tools. This is by far the easiest way to do this.

Changing brake pads is coolACCESSIBLEwhen it comes to automotive jobs. This should be done when necessary to protect your car and everyone in and around it.