Need Help- Rear brake and parking brake question

mep32jep

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I just changed the rear brakes on my 2003 LS V8. Rented a caliper tool from store and ran calipers back no problem, made sure pads ligned up with caliper "notches". Now the problem. When I drove the car, it is almost like the parking brake is too tight. I made no adjustments to the parking brake.

Do you have to adjust the parking brake after a rear brake job? If so, how do you do this?

Please help!!!
 
I guess I should clarify, when I said that it appeared that it was too tight, both wheels were smoking and you could smell the brakes burning.
 
I think it should adjust itself if you do this: Put it in park, press and hold the brake pedal then pull the parking brake switch. Then release it, put in drive or whatever and see if that helps.
 
Sounds like you didn't turn the pistons all the way in.
 
I think they were all the way in because the caliper would not fit back on if it wasn't in enough. Am I wrong in thinking that?
 
I've seen that happen with new pads that are still getting broken in. A friend's Suburban did that on the drive down to Alabama. By the time we got about 4 hours into the trip it had stopped. Still, I'd take a closer look. It would be a shame to have your new pads ruined so quickly.
 
Perhaps the caliper is stuck due to wear/corrosion. Remember that the piston is now sitting inside further than the last few thousands of miles. If the boot is damaged, it may have allowed contaminates or moisture to get in. This could prevent the piston from easily sliding and not allow the rotor to push the piston back in when you let off the brakes.
 
If both wheels are doin it I would say it is definitely aa parking brake issue. The likelyhood of both calipers failing at the same time is very unlikely. Very. Check the park brake and see if you can get it to free up. The springs on the calipers that allow it to release bind up some times. I have had to replace calipers in this situation before, but if it was mine I would take a little time to free the springs up for proper operation. And break in on a pad should not smoke like crazy. All of the brake manufacturers recomend That you drive at highway speed [65-70] and come to a complete stop 3 times and that will heat the pads enough to set the adhesive bonding agents in the pad material so they can cure. The way I do this is that I drive from the end of the street while holding the brake light enough the car will go forward and not hard enough to get super hot and warp a rotor.
 
Perhaps the caliper is stuck due to wear/corrosion. Remember that the piston is now sitting inside further than the last few thousands of miles. If the boot is damaged, it may have allowed contaminates or moisture to get in. This could prevent the piston from easily sliding and not allow the rotor to push the piston back in when you let off the brakes.

+1 On this. I was going to input the same paragraph.
 
But both calipers? same time ? Not likely at all. PARKING BRAKE SPRING ASSEMBLY ATTACHED TO CALIPER!
 
something is different

never had that problem, just cranked in the piston (with the tool) put in new pads, put it back together, and go, no problems. Sounds like an installation problem, check your work.
 
But both calipers? same time ? Not likely at all. PARKING BRAKE SPRING ASSEMBLY ATTACHED TO CALIPER!

It very well could be both at the same time since both pistons sit in further with the new pads. There are multiple things he needs to check that could be the culprit, this was just one idea. None of us know since we didn't see him do the work or know his car/ how many miles are on it. I'm not dismissing your idea.
If the parking brake was bad, I don't think he would drag the calipers until he pulled up on his parking brake.

Mep, did you remove the brake line from the caliper at all? The banjo bolts are different lengths i think front and back. Longer bolts in the rear could drag on the piston and prevent it from moving in easily.

Its possible too much fluid is in the reservoir too since you displaced the fluid with the new pads like pbslmo said. That's the easiest thing to check first. Otherwise, calipers aren't that expensive; $90 ea w core return. Slap new ones in and be done.
 
Here's an update:

I took the car to a reputable service rep locally (have used him many times before). They turned the rotors nd put new pads on (the ones put on 2 days ago were worn) He said that on of the calipers had gone in slightly at an angle and he straightened it up, put new pads on, lubed everything up and said I was good to go. Drove the car about 7 miles home and both of the back wheels were so hot that you could not touch them.

When I chaned them the first time, I did not drain any of the fluid out nor did I remove any brake lines?

Two questions: Should I have removed some fluid?
Does the parking brake have to be adjusted when changing
rear brakes?
 
bunnypancaked.jpg
 
...
Two questions: Should I have removed some fluid?
Does the parking brake have to be adjusted when changing
rear brakes?

1. I don't know. I always bleed the fluid out at the caliper when I am turning it in.
2. I have changed the brakes three times in two LSs, and I never had this issue, nor did I have to do anything to the parking brake. The service manual does not mention having to do anything to the parking brake.

I suggest that you disconnect the parking brake from both rear calipers and drive the car and see if it still gets too hot.
 
I think it should adjust itself if you do this: Put it in park, press and hold the brake pedal then pull the parking brake switch. Then release it, put in drive or whatever and see if that helps.

Have you used the parking brake at all since the pad change? Did you try the procedure I mentioned?

When I changed my pads I didn't drain any fluid but I think I did have to do the above parking brake procedure. If I recall, the message center complained about it and told me what to do.
 
I got a service brake message when I changed the pads the first time. I have not been able try your recommendation b/c the car was at the shop. As soon as I get back in town I am going to check the fluid and I will try what you suggested as well.
 
You should not have to open the brake system at all to push the caliper in. Maybe sometmes take the cap off the reservoir.
 
You should not have to open the brake system at all to push the caliper in. Maybe sometmes take the cap off the reservoir.

I always try to do this on my work so that I don't force very much contaminated brake fluid back to the master cylinder and reservoir. Check out the condition of that fluid that has been in your calipers behind the extended pistons for the last couple of years or since your last flush. It's dark in many cases. If you open the bleeder and return the pistons, you are not sending that spent brake fluid back into a system that should be clean internally. Then follow the brake job up with a flush to ensure that all the fluid is fresh and not full of water molecules. Brake fluid is cheap. Clean parts are good and may last longer.

As far as the parking brakes on these, the only adjustment is inside the caliper itself, which is what is being reset when you spin the piston back into position with a fresh set of brake pads. The electronic brake may have something up front in addition, but the calipers are not different, IIRC.

I had a set of calipers get stuck after a pad change once, and what had happened was that the pistons had rubber square o-rings in them, and when they landed back at the starting position for new pads, that area had a varnish-like buildup which caused the piston rings stick and not return from braking application, which smoked my rotors. Barring anything else being the problem mechanically, that could also be what caused the OP's brakes to get stuck on after resetting the pistons to home for new pads.
 
Owlman, tried what you said and I am not sure if it helped. I can hear the brake set and release but this has been the case all along. After doing this three times, I got the service brake message. Turn the car off and it resets.

Drove the car home tonight and the brakes did not get hot. However, it feels as though the car is being restricted somewhat while driving. I am truly at a loss on this one. I have had 2 people look at it now and it has all of us stumped. I am going to try driving it around tomorrow and hope that nothing burns ups.

Is the parking brake located inside the drum or is it part of the caliper? If it is part of the caliper, might be best to just replace them. Also, someone mentioned disconnecting the parking brake to see if that is the problem. Is this easily done? Once again, thanks to everyone for your help.
 

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