Replacing your vehicle’s brake pads and discs is a routine part of car maintenance, but ordering the correct replacements can be confusing. Many drivers assume that entering their registration number guarantees a perfect part match. 

However, vehicles with the exact same model name often feature entirely different braking systems depending on their engine size, trim level, or year of manufacture. This guide will help you understand which specifications to check, including disc dimensions and fitting positions, so you can confidently buy the right brake components the first time.

Why Registration Lookups Are Not Always Enough

A standard registration lookup identifies your car’s base details, but it often misses mid-production changes or specific factory options. During a single production run, a vehicle manufacturer might switch from one brake system supplier (such as Bosch) to another (such as Teves).

Additionally, performance trims or vehicles fitted with towing packages frequently use larger brake discs and different pad shapes than standard models. Relying solely on a model name or registration lookup without verifying the actual parts on your vehicle can result in ordering components that simply will not fit.

Which Specifications Matter When Buying Brake Parts

To ensure a precise match, you need to check more than just the basic vehicle details. Before ordering, verify the following specifications:

1. Make, Model, and Year: Essential starting points, but pay attention to the exact month of manufacture if the model underwent a facelift.
   

2. Engine Size and Fuel Type: A 3.0-litre diesel engine will typically require heavier-duty braking components than a 1.2-litre petrol version of the same car.
   

3. Gearbox: Automatic and manual variants sometimes feature different brake configurations due to varying vehicle weights and braking dynamics.
   

4. Part Reference or PR Numbers: For Volkswagen, Audi, SEAT, and Škoda vehicles, the PR number (found in the service book or boot sticker) explicitly identifies the factory braking system.

Understanding Fitting Positions and Dimensions

Brake pads and discs are designed specifically for either the front or rear axle, and they cannot be swapped.

• Front Axle: The front brakes handle up to 70% of a vehicle's stopping power. Consequently, front brake discs are usually larger in diameter and are often vented (featuring a hollow centre with fins) to dissipate heat quickly.
  

• Rear Axle: Rear brake discs are generally smaller and are frequently solid rather than vented, as they handle less braking force.

When replacing discs, the most critical specification to check is the physical dimension. You must measure the diameter and the thickness of your existing brake disc. A difference of just a few millimetres in diameter means the brake calliper will not fit over the new disc.

What the Product Includes (and What is Sold Separately)

When you order brake components, it is important to know exactly what is included in the box.

1. Brake Pads: These are almost always sold as an axle set (four pads to cover both the left and right wheels on one axle).
   

2. Brake Discs: Discs are usually priced individually but must be ordered and fitted in pairs across the axle for balanced braking.
   

3. Wear Sensors: Some brake pads feature built-in electronic wear sensors, while others require separate sensor wires to be purchased and plugged in. Check your existing setup to see if you need to order sensors separately.

4. Fitting Kits: Anti-rattle shims and calliper bolts are sometimes included with premium brake pads, but for standard kits, they may need to be reused or bought separately.

Common Ordering Mistakes and How to Avoid Them

Avoid these frequent errors when purchasing new brake components:

Mistake 1: Ignoring the Axle Position. Double-check whether you have added front or rear pads to your basket.

Mistake 2: Guessing the Disc Diameter. If multiple disc sizes are listed for your vehicle, measure your current discs before ordering. Do not assume the largest size is correct just because it is an option.

Mistake 3: Forgetting the Wear Sensor. If your dashboard brake warning light is on, the sensor has likely been triggered and must be replaced alongside the pads.

Mistake 4: Mixing Brands on the Same Axle. Always use identical discs and pads on both the nearside and offside wheels of an axle to prevent uneven braking.

Next Steps

Taking the time to verify your exact braking specifications will save you time and money. If you are still unsure which components fit your vehicle, do not guess. Contact the MDL Auto Parts team with your registration or VIN, and our experts will provide direct compatibility support.

Note: For a limited time, MDL Auto Parts is offering front and rear brake-pad sets for £40 or £60 (including VAT) for selected vehicle applications. Please call our sales team on 01708 205408 to check your vehicle's eligibility and confirm current stock availability for this offer.

Need Help Finding the Right Part?

Don’t guess on compatibility. Contact the MDL Auto Parts team with your vehicle registration and the part number you’re considering. We can help you check fitment, confirm availability, and understand what’s included before you order.

Call our team on 01708 205408. Or Browse MDL Auto Parts.

to explore our range and find your next replacement part.

Have your vehicle’s make, model, year, and engine details ready. For some parts, we may also need your VIN or the reference from the existing component.

Do I need to replace brake pads and discs at the same time?

Not always. Brake pads generally wear out faster than discs. However, if your existing discs are heavily scored, warped, or worn below the manufacturer's minimum thickness limit, both the pads and discs must be replaced together.

What is the difference between solid and vented brake discs?

Solid discs are cast from a single piece of metal, usually fitted to the rear. Voted discs feature two friction surfaces separated by cooling fins, allowing better heat dissipation. They are typically required for the front axle.

Do new brake pads come with wear sensors?

This depends on the vehicle and the pad manufacturer. Some pads have acoustic sensors (metal tabs that squeal), some have integrated electronic sensors, and others require you to purchase an electronic sensor wire separately.

How do I find out my brake disc diameter?

The most accurate method is to remove a wheel and measure straight across the centre of your existing brake disc with a tape measure. Alternatively, check your vehicle handbook or consult a main dealer.

Are front and rear brake pads the same?

No. Front brake pads are almost always larger, thicker, and shaped differently than rear brake pads because the front axle handles the majority of the vehicle's braking force. They are not interchangeable.

What is a PR number on Audi, VW, or Škoda vehicles?

A PR (Production) number is a three-character code used by VAG Group vehicles to identify specific factory-fitted equipment. Matching the PR number on your boot sticker is the only way to guarantee the correct brake parts.

What should I do if two different brake pads are listed for my car?

If a catalogue lists multiple options, check for distinguishing features like the braking system brand (e.g., Bosch vs. Teves) and whether your car has a solid or vented disc, or contact our parts team with your registration or VIN.

Do brake pads come with anti-squeal shims?

Many premium aftermarket and genuine brake pads feature pre-fitted anti-squeal shims. However, standard or budget pads may require you to clean and reuse your existing shims or purchase a separate fitting kit.