How To: Tell How Many Pistons are in a Brake Caliper

How to tell how many pistons are in vehicle's brake calipers

How to-Tell How Many Pistons My Brake Calipers Have?

Quite frequently our Brake Finder will ask “how many pistons do the front/rear calipers have?”. Don’t worry! You probably don’t even have to take off your wheel to find the answer. Modern Vehicles typically have open-wheel designs to make it easy to visually confirm how many pistons the calipers have. Generally, on 1 and 2 piston sliding calipers, you can frequently see “arches” on the face of a caliper. If you count the arches, you can usually tell how many pistons are in the caliper. 4 and 6 piston calipers are a little more tricky but you can still usually see the outline of the 2 or 3 outboard pistons.

Single (1) Piston calipers are always sliding calipers that move slightly as the brake pads wear. Most have a bracket. However, on some applications, the bracket is built into the knuckle of the vehicle. Also, some rear single piston calipers have a mechanism on the back for the parking brake.



Dual (2) Piston Calipers are usually sliding calipers with brackets, but some 2 piston calipers are fixed position with opposing pistons – one on the inboard and one on the outboard side.



4 Piston Calipers are almost always going to have 2 inboard and 2 outboard opposing pistons. 4 piston calipers are usually a fixed position design. This means you won’t see the bracket surrounding the caliper as in the 2-piston caliper above. Instead of seeing two ‘arches’, you will see 2 general outlines of the 2 outboard pistons.



6 Piston Calipers usually feature 3 inboard and 3 outboard opposing pistons. They are almost always fixed position calipers without a bracket, similar to the 4 piston design. On 6 Piston Calipers, you will usually be able to see the outlines of the 3 pistons on the outboard side of the caliper.

If you have any questions you can always reach out to our tech team ( and they should be able to assist figuring this out.

Check Out PowerStop Brake Caliper Kits:
Don’t Just Stop… PowerStop!