Replacing Brakes

The piston screws in on the rear calipers.

@Suprawill1, Your calipers probably aren't bad but if the pistons have been forced they can be damaged. I haven't done brakes on my ST so I'm speaking from my experiences on other late-model Ford vehicles. Don't hold me to any of this.

I believe it's a good idea to put it into maintenance mode not simply unplug it. This is to protect the ABS system and I've heard the master cylinder but damaging the MC wasn't a concern for years. Having said that, if your bleeder screws are open when the pistons are compressed I don't think you can hurt anything. It's a really good idea to clean the boot well where it contacts the piston as the piston will be rotating on this surface and not simply be pushed in. Clean it with some Brake Clean and a brush and use a silicone spray around the seal.

A tool like the one listed below will make it easy to compress the calipers though it is not the only way. There are other $10 tools and I've seen where pistons have been butchered by using a set of pliers. You can usually "rent" these type of tools at AutoZone but they don't cost much (@$20) to own, having a set of caliper hanging hooks around is always a nice thing.

Some vehicles have both dedicated left-side (counterclockwise) and right-side (clockwise) and counterclockwise screw-in calipers others use just a clockwise screw-in on both sides. As I have done one I can't tell you what STs have. The rented kits I've seen only came with clockwise tools which is fine if that is all your vehicle has. You'll be able to determine which direction they screw in easily. If the piston doesn't turn, don't force it, try the other direction.

https://www.amazon.com/dp/B08RHMQF1Q?psc=1&ref=ppx_yo2ov_dt_b_product_details

@Suprawill1,
Integrated park brake calipers have had screw-in calipers for 25 years. You'd never have reason to know this if you haven't played with integrated calipers. Many vehicles use the drum in a rotor brake shoe park brakes and that's a different ball game.

Thanks, I won't recommend that video again. As I said, many of your chain auto parts stores will have that tool for a no-charge rent, which might help you get through this one.

The piston screws in on the rear calipers.

@Suprawill1, Your calipers probably aren't bad but if the pistons have been forced they can be damaged. I haven't done brakes on my ST so I'm speaking from my experiences on other late-model Ford vehicles. Don't hold me to any of this.

I believe it's a good idea to put it into maintenance mode not simply unplug it. This is to protect the ABS system and I've heard the master cylinder but damaging the MC wasn't a concern for years. Having said that, if your bleeder screws are open when the pistons are compressed I don't think you can hurt anything. It's a really good idea to clean the boot well where it contacts the piston as the piston will be rotating on this surface and not simply be pushed in. Clean it with some Brake Clean and a brush and use a silicone spray around the seal.

A tool like the one listed below will make it easy to compress the calipers though it is not the only way. There are other $10 tools and I've seen where pistons have been butchered by using a set of pliers. You can usually "rent" these type of tools at AutoZone but they don't cost much (@$20) to own, having a set of caliper hanging hooks around is always a nice thing.

Some vehicles have both dedicated left-side (counterclockwise) and right-side (clockwise) and counterclockwise screw-in calipers others use just a clockwise screw-in on both sides. As I have done one I can't tell you what STs have. The rented kits I've seen only came with clockwise tools which is fine if that is all your vehicle has. You'll be able to determine which direction they screw in easily. If the piston doesn't turn, don't force it, try the other direction.

https://www.amazon.com/dp/B08RHMQF1Q?psc=1&ref=ppx_yo2ov_dt_b_product_details

Here are some quick instructions on maintenance mode:

https://www.youtube.com/shorts/i46H37_W_ZM

These are DOT 4 fluid brakes.



Integrated park brake calipers have had screw-in calipers for 25 years. You'd never have reason to know this if you haven't played with integrated calipers. Many vehicles use the drum in a rotor brake shoe park brakes and that's a different ball game.

You need to stop and familiarize yourself with the process first…and hope it doesn’t freak out when you plug it back in. You have to follow the process to put it into Brake Service Mode. This will automatically retract the pistons. After you do your work you follow the process to take it out of service mode and it will automatically set the pad height correctly.
It’s a very sensitive system…I hope you didn’t screw something up.
Putting the car into service mode is the ONLY correct way to do this. Disregard every other post in this thread.

Don't know about other methods but Forscan has service procedures for the brakes to work on them.

Hi All,
Was replacing brakes on both axles. Did the front axle yesterday with no problem. Today, thinking the back would be easier, (and it should've been) I ran into a problem.
I can't compress the caliper piston so it would fit over the new pads. I made sure the brake fluid reservoir cap was off and the electronic parking brake was unplugged. I even opened the bleed screw to relieve pressure. I called and spoke with a mechanic friend and he said the caliper was bad. Ok, that happens. But when I tried to do the other wheel, I had the same problem. I find it ironic that both calipers were bad so I'm inquiring among some of you with experience to see if there's something I'm leaving out before I have to bend over and take a stealership price on 2 calipers because everyone else say's they don't stock them because they're too new on a 2020 ST. Appreciate the hits, thanks!

i did my front brake pads and rotors yesterday. i thought you only had to put it in service mode for the rears. When u was done. i started the ST to check brake pedal. I now have: Advance trac warning, uphill assist warning, pre-collision warning, parking brake system warning, and a couple others. No DTC's come up using the Torque app scanner. How do i clear these warnings?

Put it in and out of service mode did not do it. Also pulled the negative cable. No luck. Only thing i can think off is to pull both battery cables.