How To Measure VW Brake Rotor Size

Vw Vented Brake Rotors - Vw Non Vented Brake RotorsNew Vws have more options than ever and brakes are no exception. There are a variety of brake rotor sizes, brake codes, hat heights, and brake pad set-ups that can make things a little confusing. Does your Vw have brake drums and rotors? You may have to determine whether you have single piston or twin piston calipers, Girling or ATE? What about conventional or UFO style Vw brake rotors? Vented or non-vented bake rotors? Four or eight brake pads? The list can go on and on. For example between the front and rear, the Audi A6 2.8L 30V models may have up to 10 different possible brake systems.

When shopping for replacement brake rotors many newer Vw owners often become confused. What do I have? 288mm OD or 312mm OD rotors? What is my brake code and how can I find out? Blauparts would like to help you out. Below you will find some suggestions and a few pictures that can help you confirm your brake system.


Vw Brake Rotor Face - How To Determine Vw Brake Rotor Part Number 1) The easiest and most reliable way to ensure you're ordering the correct brake rotor is to find the PART NUMBER on the existing rotor (see image). Wheel removal is required. For verification purposes, Blauparts has begun listing the part number in some brake kit product descriptions (when multiple choices exist). Please Note: You will only find the OE part number on your 'original equipment' brake rotors. If you've had your original brake rotors replaced the part number will NOT be on the rotor. You'll need to find another way to confirm you brake setup (see other steps below).
2) Your VIN (vehicle identification number) is the key to finding the BRAKE CODE. Customers have contacted their dealer with their VIN and requested what brake code corresponds with their vehicle. Only an authorized Audi Vw dealer can access the bill of material info, which reveals what braking components that where used to build your car and the subsequent brake code. Blauparts is an independent Audi Vw parts specialist and doesn't have access to this bill of material info. We therefore cannot tell you what your brake code is.
3) If you're having difficulty determining what brake code you have, measuring the outside diameter of your brake rotor may be necessary. In most cases, by knowing the OUTSIDE DIAMETER (OD) of your brake rotor you'll be able to determine the correct brake kit. However, sometimes both the rotor's outside diameter (OD) and hat height may be needed (see below).

Measuring The Brake Rotors Outside Diameter

Flip the Vw brake rotor over to its back and measure across to determine the outside diameter.

Vw Brake Rotor OD - How To Measure Vw Brake Rotor OD Size  
Popular Vw Brake Rotor Sizes Millimeter To Inches Conversion
232 mm = 9.133 in 286 mm = 11.259 in
239 mm = 9.409 in 288 mm = 11.338 in
245 mm = 9.645 in 312 mm = 12.283 in
255 mm = 10.039 in 321 mm = 12.637 in
256 mm = 10.078 in 323 mm = 12.716 in
260 mm = 10.236 in 330 mm = 12.992 in
269 mm = 10.590 in 345 mm = 13.582 in
280 mm = 11.023 in 350 mm = 13.779 in
282 mm = 11.102 in 385 mm = 15.157 in

Measuring The Brake Rotors Hat Height

To determine the hat height as listed on our brake kit description (when a hat height qualifier is noted). First, clean off a small area of rust and scale buildup before measuring the hat height. Hold a gauge across the top of the brake rotor hat. Then using a detailed measuring tool, measure the distance from the face of the brake rotor to the hat height gauge. Make sure you measure from the innermost edge, the part of the rotor face that is not worn down (see images below).

Popular Vw Brake Rotor Hat Height Sizes
Millimeter To Inches Conversion
10mm = 0.393 in
12mm = 0.472 in
25mm = 0.984 in
30mm = 1.181 in
38mm = 1.496 in
45mm = 1.771 in
Vw Brake Rotor HH - How To Measure Vw Brake Rotor Hat Height Size 1
Vw Brake Rotor HH - How To Measure Vw Brake Rotor Hat Height Size 2   Vw Brake Rotor HH - How To Measure Vw Brake Rotor Hat Height Size 3

Brake Pad Set Up Example

Vw Brake Pad Set Up - 8 Brake Pads - 4 Brake Pads