Brake Caliper Replacement DIY Guide
DISCLAIMER
As always, follow all safety protocols. Don't undertake this task if you aren't comfortable with it, fully understand it, and are capable of completing it. The information provided may be incomplete or inaccurate. You are ultimately responsible for anything you do. Neither Redpants, LLC or myself is responsible or liable for anything that may occur.
Removing the brake calipers isn’t a terribly common task but it does happen from time to time. The reason I see most often for doing this job on an Aston Martin is to recolor the brake calipers, or to replace the brake rotors, but this job may also be done if the calipers need to be rebuilt. The main calipers are really easy to replace, but the handbrake calipers on the rear rotors are a bit of a pain.
Needed
Brake caliper bolts
- 6-Piston calipers
- 4-Piston calipers
11mm hose wrench or box-end wrench
10mm hex bit with ratchet
Torque angle gauge
Rubber vacuum caps
About 1-3 hours
Torque Ratings
Brake rotor retention bolts: 10.5 Nm. (8 lb/ft)
Brake caliper bolts: 20 Nm. + 66-70° (15 lb/ft + 66-70°)
Handbrake caliper bolts: 15 Nm. + 90-94° (11.5 lb/ft + 90-94°)
Before you begin
New bolts should be used when working on the braking system. In this job, that includes caliper mounting bolts.
Torque specs sometimes include torque angle. To measure torque angle, you need a torque angle gauge.
DO NOT let the brake calipers hang from the brake hoses. The weight of the calipers can damage the hoses, even if you don't see the damage. This can result in a severe loss of braking.
DO NOT get anti-seize or anti-squeal on anything other than the surfaces that need them. If either of these get on the brake pad friction material or brake rotor surface where the pads make contact with the rotor, you can have a severe loss of braking.
DO NOT cut any corners or take shortcuts with this job. A properly-functioning brake system is an incredibly important part of safety.
Step 1
Brake the lug nuts loose on each of the wheels that will come off to change the brake pads. You don’t need to remove them entirely, just one spin will do.
Raise the car using a lift or a jack and jack stands, then take off the wheels.
Step 2
Step 3
Use the 11mm hose wrench to loosen the brake hose from the backside of the brake caliper. Once it comes out of the caliper, put a vacuum cap on the end of the hose to keep it from dripping brake fluid.
Step 4
Use the 10mm Hex bit and ratchet to remove the two bolts holding the brake caliper in place (circled in red in the picture below). Hold onto the caliper when the second bolt comes free. If you don't, the caliper will drop and can result in serious damage to the brake caliper and anything below them. Be ready for brake fluid to drain from the caliper itself when you set it down.
That’s all it takes to remove the main brake calipers. Steps 5 through 8 will cover the handbrake calipers used on the rear rotors. If you’re not removing the handbrake calipers, skip down to Step 9.
Step 5
Make sure the handbrake is fully released from inside the car.
Use the pair of 20mm box end wrenches to loosen the adjustment nuts on the handbrake cable (double-circled in blue in the pic below), then pop the cable end off the handbrake caliper (circled in red in the pic below). There's a special tool that makes this easy, but I don't have one. Instead, I pushed down on the lever and used a flat-head screwdriver to pop the cable end off the lever.
Step 6
Remove the handbrake pad retention pins and spring clip. Unlike the main brake calipers, these retention pins in the handbrake calipers are removed by pushing them outward, away from the body of the car. It can be incredibly difficult to get these out, so be careful. Once the retention pins and spring clip are out of the way, remove the handbrake pads.
Step 7
Loosen the two 13mm bolts that hold the handbrake caliper in place. These are located on the backside of the caliper. Due to limited space, I found it easiest to use a ratcheting wrench on one and a socket on the other.
Note: You do not need to pull the bolts free from the caliper. Once they are loosened enough for the caliper to come free, just move the caliper away and leave the bolts in the caliper.
Step 8
With the handbrake caliper free, you can now wind the handbrake caliper piston back into the caliper. Use a caliper piston winding tool to do that, then set the handbrake caliper aside.
Step 9
Reassemble everything! Install the brake calipers using new brake caliper bolts. Install brake pads and pump the brake pedal a few times to reseat them. If you’ve remove the handbrakes, reinstall those and make sure the handbrake cable adjustment nuts are tightened, then check the handbrake function.
And that’s it!