Caliper Question

Road mister · 2 Weeks Ago

When making room for the new pads. Do I turn the piston Clock wise or Counter clock wise?

mongeonman · 2 Weeks Ago

I have never done the brakes on my reatta but i have done many on GM models and never seen one that you have to turn the piton to get it back in place,usually just have to push it back using a C clam.i know that on VW s you have to some how turn it.

NEMO · 2 Weeks Ago

You have to turn clockwise.Looking at the piston.I have not done them in a while. Always use caliper grease to lube the pins,I push some extra in the little boots.

Road mister · 2 Weeks Ago

Thanks Nemo, I eventually gave up on the old rear calipers, they had seen there day.
There was such limited response to this, I will suggest some do's and dont's, hopefully to save others some of the added expense and time I just went through.
The rear calipers are integrated with the emergency brake, a threaded stem inside rachets them out with pad wear. An inexpensive tool is needed to screw them back down. A C-clamp is good for the fronts, but will damage the rears.
The rachet mechanism is spring loaded, turning them them wrong way will pop them apart, and their not worth fixing. You will be in good shape if they back down for you and all you need to do is pop in the new pads. If not.
After the rebate of the core charge, each new caliper's final cost was $43.00 (Pep Boys rebuilt's)
And then the added work that goes with changing them.

89REATTAJIM · 2 Weeks Ago

Sounds like a pretty good deal. Let us know how they work out. Were these "loaded" calipers (with pads)? ... Jim

Road mister · 2 Weeks Ago

No Jim, the pads were another $22.00 for the rear set. I recommend these inexpensive ones. They don't last as long as some of the ceramic pads offered but they are less wear and tear on your rotors. Suppliers may have other views, but they want to sell rotors also.

padgett · 2 Weeks Ago

I just use the cable lever to unscrew the calipers. Do nee a nut on top to keep them fron just disappearing inside. I forget which way you turn but it makes the stem go into the caliper.

Barney Eaton · 2 Weeks Ago

I follow the same route as Padgett.......... I have never had any luck turning the piston....I don't have the official tool but have tried several methods and the piston never wants to turn.

Below is a sketch I made that shows the piston and it's parts.
The stud to the right attaches to the parking brake bracket. When the parking brake is used, the internal parts are supposed to self adjust the piston to allow for pad wear and keep the parking brake in adjustment.

What usually happens... dirty brake fluid gums up the parts and they don't adjust.
You can fix the parking brake by removing the nut and bracket(lever) then turn the nut in the direction that it would turn when the parking brake cable was pulled. This is sometimes necessary when you live in a state with safety inspection and your parking brake is out of adjustment.

Now the original question about getting the piston to retract. If you read and understand the above.... then when you install new pads, you need to get the piston to retract. It will not just push in because that threaded stud will not allow that to happen.

You must remove the parking brake nut and lever. Using a "C" clamp or pry bar, push the piston in.... with pressure on the piston....turn the hex part of the screw "IN" this would be in reverse of the direction the cable pulls. What you are doing is screwing the threaded stud into the piston and the piston will move in as you screw the screw in.

When you get the piston fully retracted, you can install the new pads, and attach the parking brake lever and nut.

The second picture show the end of the stud with the nut removed... note the stud and parking brake lever fit together via a hex.

BrentS · 2 Weeks Ago

Interesting.........I did the rear brakes a few months back, and simply pushed the piston back with a piston tool (i.e. c-clamp style). It seemed to push in, just as any other caliper. Maybe mine aren't "self adjusting" anymore???
I just followed the service manual, which did not seem to describe turning the piston, or tuning this adjustment bolt. They just show a pliers, to push the piston in (figure 5B7-8).
My Parking Brake seems to work, too. Sets in under 3 1/2 pumps. Maybe I just got lucky this time.

handmedownreatta · 2 Weeks Ago

i noticed a while back that my parking brakes do nothing.i will try that.