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Dragging brakes

ngrome

Full Member
Joined
Sep 7, 2016
Messages
144
Location
Chicago, IL
Hi all, my brakes started recently dragging since it started getting cool here in the Midwest. I believe it's at the front passenger side where I'm hearing drag, like it's not releasing when the brakes applied, but they do after a few seconds or you can't hear it at high speed but you can hear it at around less than 20 mph.  The frozen caliper was just replaced in this spot (front passenger) and semi-metallic pads were put in (could it just be the cause for the noise?).  No loss of brake fluid in the master cylinder.  I do have the typical ABS/ebrakes light on issue, could that be the cause as well?  I currently have the ABS fuse pulled out so it won't be pulsating at low speed.  Any ideas would be appreciated given these conditions. Thanks in advance.
 
If dragging they would get very hot and you can smell them or feel them.

Are you sure it is not the Parking brake shoe in the rear rotor hats dragging like it tends to do on all 2002 trucks?
 
ygmn said:
If dragging they would get very hot and you can smell them or feel them.

Are you sure it is not the Parking brake shoe in the rear rotor hats dragging like it tends to do on all 2002 trucks?

Thanks, I guess I'll have to take off the rear wheel and find out. Is that something that's adjustable or requires replacement?
 
ngrome said:
Thanks, I guess I'll have to take off the rear wheel and find out. Is that something that's adjustable or requires replacement?
I just removed the shoes... as they have a TSB for a fix but I found it is not so great and they can still drag....  makes a sound like shhhhhhhhhhh shhhhhhhhh shhhhh shhhh...

And upon inspection you will find the friction material worn away and the metal backing cutting into the rotor hat which is dangerous since if it gets too thin it can cut thru and you lose rear brakes and would have one hell of a mess.
 
If it's not the parking brake, get yourself an inexpensive laser thermometer from Harbor freight.  After driving for a period of time, the rotor with the dragging brake will be much hotter than the other corners (ask me how I know  :beating: :E:).  Once you isolate the corner, it could be a few different things.  Either the pads aren't moving freely on the caliper, the slide pins are sticking. the rubber hose is old and clogged or the caliper piston is sticking.  The last two obviously will require replacing the parts.  f you replace the caliper, I would also replace the hose for good measure. 

If the pads or slide pins are sticking, get them squeaky clean with brake cleaner.  Make sure you clean the inside of the caliper into which the slide pins slides.  Then make sure they are well lubricated using brake lube.

If you do find yourself having to replace the hoses, be careful with the two 10mm bolts that hold the hose to the control arm.  Those bolts are very weak.  I snapped the head off of one on each side of the truck.  Make sure you pre-treat it with multiple doses of PB Blaster first. 
 
You say you have the ABS / Parking brake light on, have you checked the condition of the front hub bearings?  If you have a bearing going bad, this could cause all of the symptoms you are describing.  I had the same thing with my Avy about 3 years ago with the dragging feeling and could kinda hear the brakes at lower speeds.  The front hub/bearing got so bad that there was about 1" of play on the total height of a 34" tire although my ABS light never came on nor did the ABS ever even pulsate while the bearing was going bad.  Pulsating ABS at low speeds is usually caused by the ABS sensors either getting dirty or the wheel bearing is going bad.  FYI Rock Auto has SKF bearings for a real good price, I ordered and had 2 shipped here to Winnipeg and it was only about $80 more for both versus 1 (one) from the stealership.
 
Caliper slide pins can freeze causing sticking brakes as well as if the clips are not installed in the calipers that allow the pads to slide within the caliper.

Very important to use Caliper Slide grease to prevent this.

The other items mentioned can do it as well as bad flexible lines too.

Rodney
 
Look on frame right under drivers seat if wet with oil you got the poop GM rusty brake lines  Easy one day fix
As oil do not compress and air do brakes drag if you luck just bleed
Ps just cracking line at brakes to bleed is horse poop get a second person to pump em up hold on then crack line
Another post I explain my rusty brake line fix if there oil on frame under drivers seat
Good luck
Ps if oil discolored bleed all four as heat brake down oil
Ps brake oil is hydrodynamic air is air lol
 
ygmn said:
If dragging they would get very hot and you can smell them or feel them.

Are you sure it is not the Parking brake shoe in the rear rotor hats dragging like it tends to do on all 2002 trucks?

ygmn said:
I just removed the shoes... as they have a TSB for a fix but I found it is not so great and they can still drag....  makes a sound like shhhhhhhhhhh shhhhhhhhh shhhhh shhhh...

And upon inspection you will find the friction material worn away and the metal backing cutting into the rotor hat which is dangerous since if it gets too thin it can cut thru and you lose rear brakes and would have one hell of a mess.

First of all, Happy Thanksgiving to everyone, hope you fill up on turkey, stuffing, and the good stuff. I had nothing better to do than work on the truck this morning, and I isolated the dragging brakes to one wheel, the rear passenger.  I took the wheel off for another reason but did not check where the parking brake shoe was because I had to cut my work short with Thanksgiving activities to tend to.  So, how do you remove the shoe?  Anyone have a link to a video or some instructions?  TIA
 
ngrome said:
First of all, Happy Thanksgiving to everyone, hope you fill up on turkey, stuffing, and the good stuff. I had nothing better to do than work on the truck this morning, and I isolated the dragging brakes to one wheel, the rear passenger.  I took the wheel off for another reason but did not check where the parking brake shoe was because I had to cut my work short with Thanksgiving activities to tend to.  So, how do you remove the shoe?  Anyone have a link to a video or some instructions?  TIA

Well I found it on YouTube, so forget about instructions on how to get to the shoe, looks like you got to remove the whole rotor and caliper assembly.  But is there a way to adjust the brake shoe by backing it down so it doesn't drag up against the rotor, without removing the rotor?
 
ngrome said:
Well I found it on YouTube, so forget about instructions on how to get to the shoe, looks like you got to remove the whole rotor and caliper assembly.  But is there a way to adjust the brake shoe by backing it down so it doesn't drag up against the rotor, without removing the rotor?

Well, the answer to my question is no, I had to remove the rotor. I ended up having to remove another frozen caliper. I'm afraid to see what's on the rear driver side when I change the pads, but I at least don't hear any dragging. I may have to just change the hardware bolts due to the rust.

So I have another question, what if the parking brake shoe adjuster seem frozen due to rust, how do you free it up or can it be replaced.
 
ngrome said:
Well, the answer to my question is no, I had to remove the rotor. I ended up having to remove another frozen caliper. I'm afraid to see what's on the rear driver side when I change the pads, but I at least don't hear any dragging. I may have to just change the hardware bolts due to the rust.

So I have another question, what if the parking brake shoe adjuster seem frozen due to rust, how do you free it up or can it be replaced.

The dragging brake issue is very common.  That's why "some" service the clips & pins, every year.

Another recommendation is to exercise the parking brake, once a week.

So, if the parking brake seems frozen.......does that mean the pedal won't move?  Sometimes, the issue is with the pedal, rather than the shoes.  Also, there are probably four (4) cables between the pedal & the shoe mechanism.  Any of them could be frozen.
 
Found the problem, another caliper, rear passenger, was frozen plus the clip that held the ebrake shoe in place broke off due to rust so it was leaning into the rotor wall scraping, and the inside pad was also worn down metal to metal with the inside part of the rotor pretty worn thin as well. What a mess and neglect by my bro-in-law, that truck deserves better for what he paid for back in 02 (listed at $38K).  Replaced the whole caliper plus the bracket, as it only costs $8 more with the bracket, also a new rotor and pads and bought the ebrake hardware clip while retaining the old shoe.  Taking the bolts off for the bracket was a b---ch, but after some pounding on the wrench and PB blast I broke them loose.  So while I was at it, I was a glutton for punishment and checked the driver side rear brake assembly (the fronts were already worked on), and I had to use the new set of pads anyways since they come in pairs.  Also took off the bracket on that side but did not replace, only the pads, as there were no signs of rubbing, but based on the pad wear it looks like that driver's side rear caliper will need replacing soon as well.  Those pads were a pain to put on too, I would have grinded the tips down a little if I had the patience but just pounded them in after lubricating the sliders that they're supposed to pop into.

The dust shield on both side are also gone due to rust, just broke them away, and I'm looking for some replacement shields that can hopefully snap-on instead of having to bolt on. Cleaned up everything, also rust-treated the old bracket I didn't replace but put brand new bracket bolts I happened to have on-hand as spares when doing the fronts, so it won't be a pain to take off once I have the money to change that caliper.  Looks and sounds good so far, nice to be pulling up in the parking lot at work without everyone staring at you for an annoying scraping metallic sound.  At least progress was made again.  (y)
 
If you're talking about the backing plate that the rear parking brake mounts on, Dorman has a 2 piece replacement unit that lets you install it without removing the axle. Part number is Dorman 924-213.
 
Dalefan said:
If you're talking about the backing plate that the rear parking brake mounts on, Dorman has a 2 piece replacement unit that lets you install it without removing the axle. Part number is Dorman 924-213.

Thanks man, I appreciate it!  I'll look into it and try and get them before it starts getting messy for the winter (and when I'm in the mood to remove the wheels again)  (y)
 
ngrome said:
Found the problem, another caliper, rear passenger, was frozen plus the clip that held the ebrake shoe in place broke off due to rust so it was leaning into the rotor wall scraping, and the inside pad was also worn down metal to metal with the inside part of the rotor pretty worn thin as well. What a mess and neglect by my bro-in-law, that truck deserves better for what he paid for back in 02 (listed at $38K).  Replaced the whole caliper plus the bracket, as it only costs $8 more with the bracket, also a new rotor and pads and bought the ebrake hardware clip while retaining the old shoe.  Taking the bolts off for the bracket was a b---ch, but after some pounding on the wrench and PB blast I broke them loose.  So while I was at it, I was a glutton for punishment and checked the driver side rear brake assembly (the fronts were already worked on), and I had to use the new set of pads anyways since they come in pairs.  Also took off the bracket on that side but did not replace, only the pads, as there were no signs of rubbing, but based on the pad wear it looks like that driver's side rear caliper will need replacing soon as well.  Those pads were a pain to put on too, I would have grinded the tips down a little if I had the patience but just pounded them in after lubricating the sliders that they're supposed to pop into.

The dust shield on both side are also gone due to rust, just broke them away, and I'm looking for some replacement shields that can hopefully snap-on instead of having to bolt on. Cleaned up everything, also rust-treated the old bracket I didn't replace but put brand new bracket bolts I happened to have on-hand as spares when doing the fronts, so it won't be a pain to take off once I have the money to change that caliper.  Looks and sounds good so far, nice to be pulling up in the parking lot at work without everyone staring at you for an annoying scraping metallic sound.  At least progress was made again.  (y)

The lubrication won't help, if the pads don't move freely, on the clips.  Would have been better to grind the ears, then assemble everything "without" lube, than the other way around.  

This is one of those hard lessons some of us have had to learn, over the years.

If you're opposed to grinding, other enthusiasts have reported a slightly better fit, when using Delco pads.
 
Another issue is that the Parking Brake cable WILL freeze up on you if it is not exercised on a constant basis. This is with ANY car that uses parking brake cables.

No fix other than replacing the cables or disconnecting the parking brake.

Note that calling it an Emergency Brake is wrong. It is NOT intended to stop your vehicle and won't do a good job of it if you are moving at all. It is intended as a parking brake only. Most of us depend on the truck being in park and that the pin that is applied when in park will hold it. If you use the parking brake all of the time when you park it MAY help prevent the parking pin from breaking in the transmission. Realistically only useful if parking on a hill.
 
redheadedrod said:
Another issue is that the Parking Brake cable WILL freeze up on you if it is not exercised on a constant basis. This is with ANY car that uses parking brake cables.

No fix other than replacing the cables or disconnecting the parking brake.

Note that calling it an Emergency Brake is wrong. It is NOT intended to stop your vehicle and won't do a good job of it if you are moving at all. It is intended as a parking brake only. Most of us depend on the truck being in park and that the pin that is applied when in park will hold it. If you use the parking brake all of the time when you park it MAY help prevent the parking pin from breaking in the transmission. Realistically only useful if parking on a hill.

Well said.

Back in the day, there were styles that could be applied incrementally for emergencies, but not this one.
 
Nick@Night said:
The lubrication won't help, if the pads don't move freely, on the clips.  Would have been better to grind the ears, then assemble everything "without" lube, than the other way around.  

This is one of those hard lessons some of us have had to learn, over the years.

If you're opposed to grinding, other enthusiasts have reported a slightly better fit, when using Delco pads.

That stinks, I may have to pop those pads out and grind them then.  It is actually fine on the one side I changed the whole rotor and caliper, but the one side where I changed the pads only it would have been better to leave off the shims, as the thickness of the shims made the fit really tight, but I know that's not recommendable either.  Are pads supposed to be loose on the clips, or at least snug?  I am also concerned that if I grind the ears to short, it will just jostle around the caliper. I would hope that the caliper pistons are strong enough to squeeze the pads onto the rotor despite the tight fit.  But please educate me on brake operations, are the caliper pistons supposed to retract once the brake pedal is released, or do the pads just stay in the position they are in each time they are squeezed onto the rotor?
 
The pads should more or less float in the bracket, with very, very little resistance. Disc brakes do not have any type of mechanical re-tractor for the pads. On drum brakes there are at least springs that pull the pads away from the drum when there is no hydraulic pressure on the piston.
If the pads are a tight fit, yes, the caliper may be able to apply enough pressure to move the pads, but they will not ease up their pressure on the disc when you release the brakes.
 
Proper procedure is to dry fit pads on clips, before lubing.  No resistance should be encountered, or pads won't retract, properly.  When everything fits properly, remove pads, apply lube, & reassemble.

The seal which is captive in bore has a square crossection.  It bends or twists when brake is applied.  When brake is released, it springs back to its original shape.  This provides the retraction.

It isn't much, just enough.

 
Dalefan said:
The pads should more or less float in the bracket, with very, very little resistance. Disc brakes do not have any type of mechanical re-tractor for the pads. On drum brakes there are at least springs that pull the pads away from the drum when there is no hydraulic pressure on the piston.
If the pads are a tight fit, yes, the caliper may be able to apply enough pressure to move the pads, but they will not ease up their pressure on the disc when you release the brakes.

Nick@Night said:
Proper procedure is to dry fit pads on clips, before lubing.  No resistance should be encountered, or pads won't retract, properly.  When everything fits properly, remove pads, apply lube, & reassemble.

The seal which is captive in bore has a square crossection.  It bends or twists when brake is applied.  When brake is released, it springs back to its original shape.  This provides the retraction.

It isn't much, just enough.

Thanks for your replies, I think it warrants enough to pop the wheels off again and grind the tight fitting pad tabs, tangs, ears (whatever you call them) down a little so they will slide more freely within the guide rails.  Hopefully the pads won't drag and wear down too quickly after just one week of use in a six-mile commute (12 mile round trip) to work and three traffic lights in between. I was just too pressed for time that day during the Thanksgiving weekend, but it looks like I'll just have to go through the re-work.:E: Hopefully my little hand grinder is enough to do the trick. Sucks that aftermarket is not necessarily an exact fit at times. And I hope they're not going to be a PITA to take off in the process.:(
 
redheadedrod said:
If you use the parking brake all of the time when you park it MAY help prevent the parking pin from breaking in the transmission. Realistically only useful if parking on a hill.

I'd hardly call the parking pawl in the 4L60 a pin.  It's a chunk of metal about a 1/4" thick that is allowed to rotate into notches on a sprocket attached to the output shaft.  I can't imagine the likelihood of it failing to be very high at all.
 
ngrome said:
Thanks for your replies, I think it warrants enough to pop the wheels off again and grind the tight fitting pad tabs, tangs, ears (whatever you call them) down a little so they will slide more freely within the guide rails.  Hopefully the pads won't drag and wear down too quickly after just one week of use in a six-mile commute (12 mile round trip) to work and three traffic lights in between. I was just too pressed for time that day during the Thanksgiving weekend, but it looks like I'll just have to go through the re-work.:E: Hopefully my little hand grinder is enough to do the trick. Sucks that aftermarket is not necessarily an exact fit at times. And I hope they're not going to be a PITA to take off in the process.:(

I ended up grinding one set of pads down on the driver rear side because they were still tight, but surprisingly the passenger rear side pads were sliding fairly freely so I didn't touch them except to see if I can push them lightly to move with my finger, which they did, because the paint at the end of the tabs may have worn down with use over the week so they are now floating properly. The driver side was a pain in the butt, had to file down the tabs on each pad, and probably because of the old shims which I probably should have replaced in the process but I kept the old caliper for now. Funny just as a test I swapped the pads over to the opposite side of the rotor they originally were in, and it ended up being too loose so I put it back to where each one was and just filed them down until they slid in freely by hand. All's good for now.
 
redheadedrod said:
Another issue is that the Parking Brake cable WILL freeze up on you if it is not exercised on a constant basis. This is with ANY car that uses parking brake cables.

No fix other than replacing the cables or disconnecting the parking brake.

Note that calling it an Emergency Brake is wrong. It is NOT intended to stop your vehicle and won't do a good job of it if you are moving at all. It is intended as a parking brake only. Most of us depend on the truck being in park and that the pin that is applied when in park will hold it. If you use the parking brake all of the time when you park it MAY help prevent the parking pin from breaking in the transmission. Realistically only useful if parking on a hill.

^^This^^.
The parking brake CAN be used to slow down and stop the vehicle in an emergency, but it won't do it if the damn cables are seized.
But, like redheadedrod said, that is not what it was designed for. It is designed to hold your vehicle in place when parked.
People - use the parking brake. It will keep it freed up and working properly, and it may save your butt from a roll-away someday if a part in the driveline fails.
However, I suspect we already know this  >:D

CarMech1969


 
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