[brycerichert]

Can somebody explain the need to twist the rear piston in as appossed to just compressing it? I've never seen this before. It seems odd. What is the purpose? Does it "twist" out when the fluid pushes it out?

I'll accept it... the brakes are off the rear and it is just sitting there. But it appears I need to go to autozone or the dealership and get a tool that will turn that thing in.

 

[clinton2003]

basically its for the e-brake as far as i know.

 

[brycerichert]

Here is something I found from an "answers wiki", not sure if it is sound advice or not, but it would be nice to know how it works, or why it works... seems like an extra step in the design, or an extra step for retracting pistons. But I'm not an engineer. There is obviously something I'm missing.

<quote>

You have to turn it (caliper piston) as you are depressing the piston back into the caliper. You can't just "jam" it in. I used a caliper tool (for depressing the caliper) and turned the piston with large jaw pliers. This gives both inward pressure and the turning motion. I turned it clockwise and that seemed to work. There is a special tool you can buy to turn the piston as you push it back into the body of the caliper but if you work carefully and you are VERY aware of the rubber boot (don't rip it) then pliers are ok (don't tell the Ford dealer). Cover the pliers with something so you don't scratch/ruin the piston. The front brakes are just a standard push - don't need to turn them. Why do the back brakes work this way? Has to do with the parking brake. If you look you can see that it is attached to the caliper on the rear.

/

 

[pdmustgt]

Has to do with e-brake being inside caliper as pads wear they ratchet out or you loose adjustment on e-brake. They do make style that e-brake not part of caliper like Explorer rear disc they have parking brake shoes on inside of the rotor. This of caliper you just push them back in.


You better off buying right tool to do them tends to ruin pistons if using anything else

 

[OAC_Sparky]

Has to do with e-brake being inside caliper as pads wear they ratchet out or you loose adjustment on e-brake. They do make style that e-brake not part of caliper like Explorer rear disc they have parking brake shoes on inside of the rotor. This of caliper you just push them back in.


You better off buying right tool to do them tends to ruin pistons if using anything else

This. Personally I use an adjustable spanner that I use on various tools (like an angle grinder) that works well.

Like this:

 

[Plumbago]

Done this, but be sure to turn them the correct way. One side is clockwise the other counter clockwise, can't remember which is which.....there is a good video on utube about doing this....Adjustable channel lock pliers and a large C-clamp worked well for me..............Plum

 

[FirstFord94]

This is not really an uncommon thing. The ATE-branded rear brakes on my VW Corrado are the same way. I'm surprised they aren't that way on your e46.

I used one of those "special" tools from pepboys/advanced auto/whatever and it worked great on the VW. I suspect it will be just as easy for you on the mustang once you get the right tool.

 

[Rascal]

Take the cap off the master cylinder it makes it easier for the fluid to return while turning the rear pistons back into the caliper. It also allows the piston to stay turned back into it's normal position.
Obtain the RIGHT TOOL for the rear pistons. Available at any quality parts store. Pep Boys ,Cragan, Napa. It's around $8.00. Make sure the area of the caliper is clean and free from dust ,etc. Position the tool squarely on the piston with the two small prongs seated. Press inward toward the caliper while turning clockwise, using a 3/8 ratchet and small extension. Be careful and take your time. There is a small tab on the tool this tab lets you know the position of the piston as it is rotated. When the piston is seated back into the caliper, align the tab of the tool at 12 o'clock position so that the new brake pads will drop right in and seat in the caliper. If you replace the rotors clean the bracket bolts apply a drop of blue loctite and torque the bracket bolts to 76 Ft Lbs. (This torque is for the large bracket bolts only not the small caliper bolts) Top off the master cylinder and replace the cap.

 

[Cstrahan]

I changed my rear brake pads and used the proper tool. It's easy. Auto Zone has the caliper retracting tool set and they let you use it for free.

 

[Cstrahan]

Oh yea NAPA could not help me.

 

[brycerichert]

Thanks for the insight people. The scratching on the piston is my first attempt to only turn it in with grips... that was a no-go.
Here's the $10 item I picked up. The guy at autozone said it would work on any mustang rear brakes. Had to take it back.. too good to be true.

The pictures after that are what actually worked. The parking brake integrated design actually makes sense now.

It didn't fit all the way on.

Went back and picked this kit up for $60. I've got a lot of sizes I'll NEVER use.

 

[brycerichert]

I couldn't seem to find this $8 tool.

Take the cap off the master cylinder it makes it easier for the fluid to return while turning the rear pistons back into the caliper. It also allows the piston to stay turned back into it's normal position.
Obtain the RIGHT TOOL for the rear pistons. Available at any quality parts store. Pep Boys ,Cragan, Napa. It's around $8.00. Make sure the area of the caliper is clean and free from dust ,etc. Position the tool squarely on the piston with the two small prongs seated. Press inward toward the caliper while turning clockwise, using a 3/8 ratchet and small extension. Be careful and take your time. There is a small tab on the tool this tab lets you know the position of the piston as it is rotated. When the piston is seated back into the caliper, align the tab of the tool at 12 o'clock position so that the new brake pads will drop right in and seat in the caliper. If you replace the rotors clean the bracket bolts apply a drop of blue loctite and torque the bracket bolts to 76 Ft Lbs. (This torque is for the large bracket bolts only not the small caliper bolts) Top off the master cylinder and replace the cap.

 

[Deadstick]

Harbor freight!
18 Piece Disc Brake Pad and Caliper Service Tool Kit
Get it on sale, and then use the 20% coupon in the back of just about any magazine.

 

[brycerichert]

Holy cow! thank god for china. I'll order that now and take this one back... it's less than half the price. thanks for the link.

Harbor freight!
18 Piece Disc Brake Pad and Caliper Service Tool Kit
Get it on sale, and then use the 20% coupon in the back of just about any magazine.

 

[SpeedKing-713]

Can somebody explain the need to twist the rear piston in as appossed to just compressing it? I've never seen this before. It seems odd. What is the purpose? Does it "twist" out when the fluid pushes it out?

I'll accept it... the brakes are off the rear and it is just sitting there. But it appears I need to go to autozone or the dealership and get a tool that will turn that thing in.

Bryce, just curious how many miles do you have on the Mustang? Did you change to 'upgrade' or did you need rear pads already?

 

[brycerichert]

Bryce, just curious how many miles do you have on the Mustang? Did you change to 'upgrade' or did you need rear pads already?

24xxx and it just started squealing a few days ago, the pad was totally shot, and the snub that squeals before the brake pad backing hits the rotor seemed to not have been aligned correctly. I saved the rotor, but have a set on order.

These rear pads have seen some accidental track days, so I'd say they would have gone 30,000 or so.

 

[brycerichert]

This sums it all up!

http://www.autoshop101.com/forms/brake06.pdf

 

[YerBuddysPony]

Yeah, I'd say that pad is shot. I'm surprised the rotor isn't a total loss as well.

 

[Swoope]

to funny,

i have the block tool to put my rx8 rear pads back in place. just required pressure and the right direction of rotation...



beers

 

[Cstrahan]

Bryce, That is the same kit I used from Auto Zone. Did you have to buy it? They just made me pay the $60.00, but let me return it and refund my money