Brake Pad & Disc Calculator - Your Guide To Car Brakes
How do car brake pads and discs work?
Brake pads and discs work together in their crucial role, applying the frictional pressure required to slow your car.
- Brake pads apply the pressure required to create this frictional force, clamping down on the brake disc to slow the vehicle. They are usually found attached to one side of the brake disc and apply a vice-like grip to the brake disc when the brake pedal is pressed. While they are robustly built, this continual friction causes wear to brake pads and over time they become thinner until eventually they will need to be replaced.
- Brake discs are the other frictional component in your car's braking system. They are the circular disc the brake pad clamps to. Brake discs come in 2 main types, slotted or drilled. The reason they are slotted or drilled is to provide a route for heat, gas or liquid to escape the brake disc surface, increasing the efficiency of your braking system. Over time, brake discs will eventually get thinner due to the frictional forces applied by the brake pads, which results in overheating and reduced efficiency.
Keep scrolling to use our brake calculator and find out how to book your own FREE brake check...
MotorEasy's Brake Calculator - check your remaining brake pad & disc lifespan
How long do car brakes last?
- Car brake pads last around 50,000 miles on average, but this can vary depending on a large range of factor which we've detailed below.
- Car brake discs generally last longer than brake discs, again this will vary depending on a number of factors.
What factors affect brake pad and disc wear?
- Where are you driving? Motorway driving requires less braking than inner city journeys with lots of stopping and starting.
- What is the car carrying? Lots of passengers and keeping power tools or golf clubs in the boot will add weight to the car, increasing the frictional forces required to stop the car and increasing your brake pad & disc use.
- What type of brake pads do you have? Organic brake pads are cheap but don't last. Low metallic pads are noisy but last longer. Semi-metallic brake pads should last longer again, and ceramic pads last longer but will cost you the most!
- How often do you use your car? This one is easy to figure out - if you are driving more your pads and discs will be used more, and you'll need to replace them faster.
- Where are the brakes on the car? Front brake pads and discs tend to wear out faster than their rear equivalent, as more of the car's load moves to the front on braking (this is why the front of the car dips when you brake hard!)
How long do my car brake pads and discs have left?
At your MOT test and annual car servicing garages will usually tell you what's left on your car's brake pads and discs. They'll usually tell you this information in one of 3 ways:
- Mileage left - This is the most useful information to be given in our eyes. Having an estimate on how long your brakes and pads have left is useful as it'll help you plan ahead for brake pads and disc replacement.
- Depth left in mm - The garage can easily take these measurements and give them to you. It'll appear on most health checks (including ours) and entering the depths into our Brake Calculator above will give you an estimate of how many miles these components have left before you'll need to change them.
- % Worn or % Left - Unless you've got a certain level of mechanical understanding this won't mean much to you and can cloud what should be a simple piece of information. We advise asking for further clarification if you're given a %. Ideally how many miles are left on each before you'll need to replace them. If you're given measurements you can lookup your car on our Brake Calculator above to get an estimate of the remaining mileage left.
When do my brake pads and discs need to be replaced?
Brake pads and discs need to be replaced when the frictional surfaces gets too thin to be safe. Most manufacturers will advise when your brake pads and discs need to be replaced - you can find this from your handbook or using our handy Brake Calculator above. You can also look out for these brake warning signs:
- Brake Pad Wear Warning Light - you don't need to be a mechanic to notice this one. If your car's showing a brake pad warning light on the dashboard get a brake pad replacement booked in as soon as possible. This isn't the case for older cars or all new models though, so don't rely on it.
- Visual Inspection - it's possible to check your brake pad depth yourself through the spokes of the wheel. You're looking to measure the depth of the outside pad pressed against the brake disc. Check your car's minimum brake pad and disc depth using the handbook or our brake calculator above.
- Loud Screeching Noise - if you're hearing this when braking you're getting to the end of your brake pad's lifetime. If it's a grinding noise getting brake pads replaced is even more urgent - book a brake pad repair.
- Pulling to one side - one of the reasons this can happen is due to brake pads or discs wearing too thin. Check the depth or get a free brake check booked.
- Brake pedal vibration - brakes can generate extreme heat due to the friction created, this can even warp the brakes. When this happens you'll often feel this as the brake pedal will vibrate when applied.
How to extend the life of your brake pads and discs
These simple steps will reduce wear & tear on your pads and discs to save you money in the long term and keep you driving longer:
- Remove unnecessary weight from the car and boot, leave the golf clubs and power tools at home unless you're using them!
- Reduce heavy braking by coasting to junctions and planning ahead when you can see traffic developing and will need to slow down. Sudden braking and harsh decelerating increases the rate of wear on your brake pads and discs.
Brake pads, discs and the MOT test
Brake pads and discs are a legally required check at your annual MOT test.
Brake pads, discs and servicing
Brake pads and discs will be checked as part of your car's annual car servicing.
Book Your FREE Brake Check
If you're unsure whether your pads and discs are worn or need replacing don't worry - you can book a FREE Brake Check at your local MotorEasy network garage today. We'll help decide whether it's the right time to change your pads and discs as well as saving you money on parts and labour costs using our trade discounts.
To book your free brake check simply hit the link below, enter your details, select "Free Car Inspection" then "Brake Check" when prompted.
Lost In Translation
Head to the Lost in Translation hub for more handy guides and advice for your next trip to the garage.