wildwilly1

changed summer wheels and tires out to winter. just a straight wheel change.unbolt summer bolt on winter. had car in jack mode with emergency brake on while doing this. got all changed went to drive to check it out now emergency brake will not release. i can hear the motor work when i try to release it with button in car but no release need help urgent car will not move ?

MP4.2+6.0

I haven't ever had a balky issue with these, but I set the brake regularly.

In your case, rather than some kind of disassembly, I would probably just try the tried and true physical method first. Take the two rear wheels back off and give the brake area some whacks with a rubber mallet. I would hit just the main caliper (metal) area, not the parking brake motor specific area. That is plastic and you don't want crack it. The objective is more just to set up some vibration to free stuff up, without damaging or bending anything.

Panelhead

Is there a way to lubricate the brake motor s to make them move freely? I do not use mine much, and think sometimes they release, but not all the way.

mishar

+1 on a rubber mallet...

If that doesn't work you have to take off brake motors and manually release the brakes. It can be only one side. Check if you can hear both motors working. If one is disconnected for some reason it is quite a problem.

mishar

Can you push your car on a leveled surface with parking brake relished and transmission in N?

MP4.2+6.0

For motor itself, not sure. Some have taken it apart for other reasons, but I just leave it be since it works 100% on mine.

I had a rear caliper basically freeze up on my C5 4.2, which has essentially the same rear brake calipers but with the conventional cable. It first I thought it was a kid not releasing brake. Did a pad replace, but more wear. Took it to gas station just down the street one day (car was cold) and filled up. I noticed right rear brake and wheel area was already very warm/hot. Didn't make sense since it was just a stop or two at 25-30 in residential area, parking brake was off. Other rear rotor was still almost cold. I quickly confirmed it was locking up internally somehow, and this set up was with the mechanical parking brake where you wind the piston back in when doing a brake job. Older car by then, so I just got a used one and quickly installed. Logically it could either have been the piston starting to get balky in its cylinder--those also have to rotate over time for the pad wear adjustment--or it was something in the the parking brake mechanicals in the caliper unit that apply the force to clamp the rotor.

What that situation was not--but you also have to pay a bit of long term attention to as well--are the sliding pins to which you bolt the caliper to the bracket that in turn bolts to the hub area. Those should get greased under the rubber bushing with a pad change, and they sell the bushings (and bolts, and pad shims too) as piece parts if they wear/get torn. You also want to look at the caliper sliding in general; If something in the sliding function (a "floating" design driven by single piston on only one side quite basic set up) hangs up, a sign of issues there tends be uneven had wear from side to side, or sometimes the wear isn't square to the pad backing plate.

wildwilly1

well got it fixed. did one very stupid thing to cause this. when i changed the wheels i put the wrong longer lug bolts in. i guess you could chalk it up to my blond moment. changed them out to the shoreter ones all is good now. very stupid on my part. thanks to all you guys who commented on this very nice of you thx a lot .