Have a '94 chevy lumina 3.1 sedan i think we need to start thinking about changing the rear brakes and rotors on. The trick is (and i remember this once before) once the rear calipers were relieved of their old shoes, i could not compress the piston back IN, so that that new shoes would fit over the rotor. At the time, rear calipers were fairly expensive and this was a fairly new car. NOW, rear calipers costs about 30 bucks a peice with a core.

Objective: I dont WANT to go replacing the rear calipers again. Do i have to releive the caliper of brake fluid before the piston goes back in?


Hints and tips are apreciated.

Did you try a large C-clamp and an old pad to push it back in? If that doesn't work, put a hose on the bleed valve running to a can or jar. Open the valve and try again with the C-clamp. But really, the clamp should force the fluid back up into the master cylinder.

Of course, if you have topped off the master to compensate for the amount that is filling the wheel cylinders because of the worn pads, it will overflow the master. You can remove some fluid by slowly inserting a paper towel and pulling it back out loaded with fluid. Be careful to not drip it on any painted surfaces. Have a drain pan right next to (or under if possible) the cylinder to put it into. Clean up any that you spill right away.

They make a special tool that allows you to turn the piston in. Don

the tool you need is not very costly at most auto suppliers. to use it you push in on the tool while turning it,there is a bolt inside the caliper and the head must be pushed into the internal socket ,this will retract the piston. AL

You will also want to make sure the caliper slides are free, it was very common for them to stick. We had a tool kit to press them out and clean the bore then install new seals.

In other words, the piston must turn as it goes in? I think this has something to do with the emergency brake.

I was told that only the dealer has this tool to retract the rear caliper piston.

the tool is available at any tool supply, it is a square with pins on all sides for other makes and fits 3/8s drive ratchets.AL

so THATS what the box is i see at sears...damn...how simple!

Harbor Freight sells the caliper tool you need.

http://www.harborfreight.com/18-piece-disc-brake-pad-and-caliper-service-tool-kit-97143.html

Its cheap, easy to use and makes quick work of them. Those W-body rear calipers usually freeze up though. Make sure you lube all the parts you need to lube with good grease and make sure the e-brake cables are free & working. That's what keeps those rears adjusted if I recall. Good luck!