Step 1 of 10
Replace brake pads step 1 of 10: Turn the steering to full lock
With the car safely on an axle stand and the wheel off, turn the steering wheel to full lock, so the front of the hub turns in and the back of the caliper, with its guide bolts, swings out where you can reach it.
Tools: none, just your hands
All 10 steps
- 1Turn the steering to full lock
- 2Open the brake fluid reservoir
- 3Undo the lower guide bolt
- 4Swing the caliper up and hang it
- 5Take out the old pads
- 6Fit new clips and grease the pin
- 7Slide in the new pads common mistake
- 8Push the piston back
- 9Swing it down and torque the bolt
- 10Pump the pedal, close the cap, refit the wheel
What you need
- New brake pads · a set for the axle, usually with clips
- 14 mm socket and ratchet · and a 17 mm open-ended spanner
- Torque wrench · set to your car’s figure
- C-clamp · to push the piston back
- Brake grease · high-temperature, for the pins
- Axle stands · never work under a car on a jack alone
Questions
Which way round do brake pads go?
With the friction lining facing the disc and the steel backing plate facing away from it: the inner pad’s back against the piston, the outer pad’s against the caliper’s fingers. Brembo’s instructions warn that the friction material must face the disc.
How thin can brake pads get?
New pads have about 12 mm of lining. Brembo says to change them at 2 mm, Haynes at 3 mm; many pads squeal through a wear indicator before that.
Why push the piston back?
The piston creeps out as the pads wear. The thick new pads only fit once it is pushed back into its bore, which sends fluid back up to the reservoir.
Why pump the brake pedal afterwards?
With the piston pushed back, the first presses of the pedal only move it out to the pads and go almost to the floor. Pump it until it is firm before you drive.
Do I change the pads on one wheel only?
No: brake pads are changed in pairs, on both wheels of the same axle, so the car brakes evenly.
Safety
Brakes stop the car: if you are not sure, have a garage do it. Work on level ground with the car on axle stands, never under a car held only by a jack, and chock the wheels that stay on the ground. Never let the caliper hang on its hose, keep brake fluid off paint and skin, and do not drive until the pedal is firm.
About this guide
This guide shows a common single-piston floating caliper on a small car’s front wheel: a cast-iron bracket bolted to the knuckle holds the two pads, and the caliper slides on two greased guide pins. The steps follow Brembo’s instructions for fitting pads and Saab’s workshop manual: hold the guide pin while its bolt is undone, pivot the caliper on its other pin and tie it up so the hose takes no weight, push the piston back, and fit the pads with their friction material towards the disc.
The 14 mm socket, the 17 mm spanner and the 35 Nm are typical figures, not universal: Brembo gives 32 to 36 Nm for M8 guide bolts and 65 to 75 Nm for M10 ones, and your car’s manual has the final word. The pad thicknesses follow Haynes (about 12 mm new) and Brembo (change at 2 mm); the readings are illustrative.
Sources: Brembo: fitting brake pads, Brembo: fitting calipers (tightening torques), Saab WIS: front brake pads, replacement, Haynes: how to check the thickness of your brake pads.
The 3D models, drawings and text are our own.