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My 2004 Grand Prix GTP Comp G has a rear brake problem. I started to hear a scraping sound from the left rear ( drivers side) wheel and looking at the rim I see a lot of brake dust on it Also, recently I noticed that my e-brake pedal will not depress when stepped on, stays in the up position and will not budge. I took the wheels off both sides in the back and see that the inner pad on the left side is shot. When I use a screwdriver to move the e-brake lever on the caliper, I can move it to the engaged position but when I remove the screwdriver pressure the tab does not spring back… I have to push it back. But that’s the case on both sides, left and right, and the right side does not seem to have a scraping issue. Here’s my questions ……
1. How do I determine if it is the caliper that is stuck or a rusted/ stuck e-brake cable at the wheel ?
2. These calipers are the new type with the built in e-brake… I don’t like these ….. how hard is it to get the e-brake cable off of them and back on.
3. How do you turn these pistons back in, assuming I don’t have to replace the caliper.. since these are expensive??
4. If I have to replace the two e-brake cables going to the wheels, how hard is it to get that back together and adjusted ?
Thanks for any pointers….. I am trying to avoid bringing the car to a shop.. but I am stumped on how to decide if I need to replace the caliper or the cables or both …. Thanks..
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I’ll try to answer this as best as I can…being a Dealer tech…we didn’t see a lot of cars out of warranty..
First: Follow Eric’s brake replacement service procedure…
If I can remember back that for…hopefully I have this correct…on most GP’s you don’t have to remove the caliper assembly from the parking brake cable to replace the rear brakes. If I remember only the high performance “RPO’S” you had to. To find out which brake system you have, under the spare tire cover you’ll have a decal with letters and numbers on it. I don’t know which ones are for brakes so maybe someone on the forum can tell you.
To answer some of your questions:
How do I determine if it is the caliper that is stuck or a rusted/ stuck e-brake cable at the wheel..
Use a special spanner tool to rotate the caliper piston clockwise to retract the piston into the caliper…if you can’t the caliper needs attention. I never had issues with these types of calipers, but I worked at a dealer and never seen very many cars out of warranty….so someone else will have to fill in here.How do you turn these pistons back in, assuming I don’t have to replace the caliper..
Use the spanner tool (you can try set of needle nose pliers) to rotate the caliper piston clockwise to retract the piston into the caliper. Make sure the notches on the piston are at the 6 and 12 o’clock positions when the caliper piston(s) are retracted fully.After brakes are installed..Pump the brake pedal a few times to seat the brake pads and pump the parking brake pedal a few times to adjust the parking brake before trying to move the car. Finally check fluid in the master cylinder.
What you have to look at very close is seized rear brake caliper retaining slide pins…this was a big problem with that brake system. If you have the inner pads worn more than the outer…very likely seized pins…
JTF, Thanks…. It is the high performance GTP Comp G model. So sounds like from your reply I will need to remove the e-brake cable. My main unknown right now is how do I do that? Do I have to mess around with that rusty old tensioner adjustment assembly over where the cable from the front ties into the 2 wheel cables… or do I simply unbolt the caliper move it the right way and wiggle the ball end of the wheel cable out of it ? Keep in mind one of my two main symptoms right now is an e-brake pedal that will not depress… When I have someone try I can see the cable from the front slide out of its sheath slightly, but neither of the wheel cables budge ….. Thanks again .
[quote=”sunrise7″ post=93666]
1. How do I determine if it is the caliper that is stuck or a rusted/ stuck e-brake cable at the wheel ?Disconnect the cable where it meets the caliper (on both sides) and try the e-brake. If still seized, it’s the cable (or, unlikely, the pivot) and will need replacing. It sounds like your caliper e-brake mechanisms are a little seized too, so these may need working back and forth with some penetrating oil while the cable is disconnected.
2. These calipers are the new type with the built in e-brake… I don’t like these ….. how hard is it to get the e-brake cable off of them and back on.
Usually pretty easy, unless rust has entered.
3. How do you turn these pistons back in, assuming I don’t have to replace the caliper.. since these are expensive??
As per EricTheCarGuy, pinch off the flexi hose, open the bleeder and either use a special caliper rewind tool or (as I do) grind a piece of flat steel to fit in the caliper piston groove and wind it in clockwise while pushing hard.
4. If I have to replace the two e-brake cables going to the wheels, how hard is it to get that back together and adjusted?
I usually leave the old cable in place and gradually lay in the new one from front to back. Not too bad a job but expect to get covered in crap. As for adjustment, put everything back together and pump the brake pedal to seat the pads. See how many clicks it takes to activate the e-brake. You can then adjust it until you get a sensible number such as five.
[/quote]You have to release the e-brake cable tension on the tensioner with the e-brake released to get the e-brake cable off the caliper. I guess you tried to PT blast the tensioner? Another thing is to pry the e- brake cable caliper mechanism that controls the parking brake away from the ball on the cable and try to remove the cable…. But if you can’t save the cable, go ahead and cut it and get it over with.
Remove the calipers try (hopefully) retracting the pistons….if you can’t replace the calipers.
Sunrise:
Sorry for not answering your cable question to begin with… I was called away for something and didn’t reread my post before posting.Thanks !!! You guys are awesome. I think I am armed with enough information now to be dangerous… I will probably get to this job on Thursday.. this gives me an excuse to get out my ’84 Mazda RX7 or my ’71 Chevelle convertible [ with the gas guzzling 454 big block ] and drive them for a couple of days since they usually sit in the garage ….. But I do like my Ponti GTP too …. I will fill you guys in on any special steps needed for this job on this particular car model…. Thanks again, And Stay Dirty…
The forum seems to be on this one. I agree that removing the cables is the first step. If the parking brake lever returns to it’s proper position, then the problem is the cable and not the caliper. As for removing it. You might try disconnecting the mounting bracket to loosen the cable before removing it. In fact, this may be all you need to do to check the caliper. More information on how to push those pistons in and other information on brakes here.
http://www.ericthecarguy.com/faq/solving-brake-problems
Good luck and keep us posted.
Thanks.
I am having trouble releasing the cable at the tensioner. How does this work? Just keep turning the threaded rod attached to the end of the cable…. this is the piece that threads into the tensioner. Seems as I turn it the cable just seems to get twisted and this makes it harder and harder to un-thread it .. Know of any videos that show how to do this ?
Thanks….I don’t have a video on that sorry. I did find this pic however that might be helpful. Looks like they run a junction just before the back wheels. I believe it’s adjustable around part 11. If you can loosen it there you won’t have to worry about the parking brake pedal. In fact, it might be easier to release tension once the cable has been disconnected.
Not sure, but it sounds like you’re turning the wrong piece. Does the threaded rod go into something you can turn instead? Can you remove the whole assembly and spin it? Clean everything up a take a good look with a torch, sorry, flashlight. Take a few photos for us if you can.
The parking brake equalizer is has a threaded shaft on one parking brake cable that’s threaded into a sleeve on the opposite parking brake cable. The parking brake application pedal cable also is attached to the equalizer. Soak it overnight with a rust break….When they rust, sometimes you have to cut them out and replace.
Hopefully this link will help…It’s a “W” body Chevy…same application as the Pontiac.
http://impalahq.naioa.com/HowTo/ParkingBrake.html
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