brakes dragging

[awt28]

When I spin my front wheels with them in the air, my brakes are constantly dragging on the rotors. Is that normal. I don't think it is, but I'm not sure.

If this is not normal, what can I do short of rebuilding/replacing the calipers.

Thanks for the help.

Tony

 

[Speed_racer]

nothing.

Seized caliper can be really bad dude. Dont leti t get too hot, could start fire. no lie.

 

[8Mud]

Have found gravel and sand stuck between the pad and the disc. Mud packed in around the piston, gets like cement from the heat. Won´t hardly wash out. Digging at it, can puncture the piston seal/dust boot. Spraying the mud with penetrating oil sometimes helps loosen it up.
Sometimes after putting on new brakes (moving the pistons in), with a punctured dust boot, will cause crude and rust to hang up the piston some, as it wears in (sticks).
On the early models with the rods, the caliper rides on, the insert (plastic/teflon?) can get twisted and cause the caliper to hang to one side or the other (uneven pad wear/one pad wears more than the other).
A little rubbing is normal, but there really shouldn´t be much resistance.
Using brake fluid from an open container, can get some moisture into the system (DOT 3 sucks up water from the air). The moisture in the brake fluid truns to steam at the caliper. Will really lock down the old brakes.

 

[Hawaiian Style]

I've noticed that humidity has a lot to do with brakes dragging. I don't know if it's the rotors or the semi metalic pads but something causes some corrosion. I hosed out my garage one night and BOTH my YJ and my XJ has brake problems the next day. I just hit the calipers with a hammer a couple of times to shake them out and they were fine again. The YJ brakes were a bit worse though and one was dragging real bad. HOT HOT HOT. My poor rims were baking by the time I drove it back to my garage (only two blocks).

The post about the fire is no $hit either... I had Midas do my brakes when I was in high school and they were smoking a day later. Luckily no fire but there was A LOT of smoke!

 

[HossHoffer]

Drag

A little drag is normal. The pads aren't made to back off just release the pressure so the pads stay in contact all the time. However if it is severe then the first thing to do is bleed your brakes. Air in the piston can heat up and expand as you're driving causing the brakes to seize or drag. Don't stop at the front brakes either. Bleed and clean the whole system front and back. By the way with these metallic pads, if the heat becomes too hot they have a tendency to crack and split. Anyway, sounds like you just need a good bleeding.

 

[Beached Bones]

Man am I glad I found this old thread. My front brake seized last year on a hot and humid day. It's been hot again lately and my new calipers/brakes have been dragging again. Could it be that this is all from some moisture in the fluid causing it to steam and hold the brakes on? I don't remember if the shop said they changed the brake fluid when they did the fix. I'm guessing not. (yeah yeah I know, but they seized far from home and far from my tools)

If not what else could cause two sets of calipers (passenger side) to drag? Kinked brake line somewhere?

92xj 4.0l auto

 

[Eagle]

If not what else could cause two sets of calipers (passenger side) to drag? Kinked brake line somewhere?

92xj 4.0l auto

Not kinked -- deteriorated. The rubber flex hose from the fender to the caliper can deteriorate on the inside. If this happens, a flap of rubber can come loose and act like a check valve. It can flap in a direction that impedes braking, or it can flap the other way and block the return of the fluid to the master cylinder. In the latter case, it keeps the caliper locked up.

 

[Beached Bones]

Thanks I'll replace the line and do a brake flush for good measure.

 

[Talyn]

As a previous poster said, the brakes are suposed to be incontact with teh rotor. They never fully release from them.

-Chris

 

[Dave in Eugene]

No kidding about the fire hazard. Just Friday I was in the wife's rig (Aerostar not a Jeep) and the front end picked up a hellacious wobble, we stopped and right front brake was VERY hot, a lot of smoke. It was an unusually warm day for here (104F), figure contaminated fluid boiled and built up pressure on the brake. Unsealed brake juice will draw moisture from the air which will lower it's boiling point, keep the lid on tight. Previous owner sent momma to Les Schwab to do the brakes not long before we got the van, and apparently they don't (I have a corporate account with them and they'll put their best guy on anything I send them, but my personal feeling is that you don't want to send momma to Les Schwab by herself :nosmile: - rear shocks are about to fall off, now this with the brakes - but the tires are fine).

Tire was too hot to hold, and forgettabout the wheel. Seal cooked and hot grease running out of the bearing housing made a lot of smoke, but we were lucky and had no fire, I have seen this situation go to full flame before. After cooling a half hour tried to drive and the brake made a lot of noise, jacked up and the wheel would not turn by hand. Left overnight and next morning the excess pressure was gone and the wheel turned free, amazingly the caliper still functioned and there was no fluid lost or leaking, but yeah linings were black and split into several odd sized sections, the anti-rattle backings were melted away, rubber boot on piston looked like it might have been on fire at some point, and the rotor was heat checked as bad as I've seen in a long time. Put all new stuff on from the spindles out in the relative cool (101F) Saturday, pushed new fluid through the ststem, and now all works fine and :loveu: is happy (well, civil anyway).

 

[Beached Bones]

Well....... I bled a couple squirts out of the caliper. I put the Jeep up on jackstands and ran her in 4hi. The rotor is not showing much sign of wear. Thought maybe I could see for sure. The FR brake wasn't dragging any more than the others. (at that time anyway) but like I said, it usually makes the grinding sounds when it's very hot and I'm in traffic. It's hard for me to know exactly where the sound is coming from. The jeep doesn't pull hard to either side when breaking.

So I'm still confused. I like to be as sure as possible that I've found the problem before I just start replacing parts.

 

[DenLip]

This sounds like the problem I had on a '97 Dodge Stratus... (and, yes, the ol' XJ's calipers *look* mighty familiar to me....)

I had one seize up GOOD twice... and I suspected problems a number of other times (warm wheel, hot-brake smell, etc). The second time it seized "good", I was 1000 miles from home, on a Saturday night, and planning to drive the whole way home the next day. So I was, er, visibly upset.

A friend told me the "scoop" on these Chrysler/Bendix calipers.

The calipers, with age, have problems with the fiberglas piston "bloating"... from soaking up a wee bit of fluid or such. They literally get just a thousandth or so bigger in diameter. Just enough so that WHEN THEY GET HOT, they seize in the bore.

If you drive gingerly, like I normally do... or if the ambient temp is cool enough... it will manifest itself as nothing more than an "occasional" warm brake for a long time (mine went MONTHS before I finally figured it out).
If you don't get the brakes HOT, they won't seize.

But once you DO get them warm (on a hot day, lots of stopping around-town, or whatnot), they might stick with pressure against the rotor. Then they
generate their own heat, and will not let go until they cool back to room temp.
How quickly they heat up is directly related to how hard you were pushing the brakes when they decided to seize!

The first time I smoked it, I had the car towed home... then couldn't find anything wrong with it the next morning! The second time (on vacation), I had talked to my friend who told me of the problem. After the car sat for a few hours, I drove back to the motel without any problem... then I drove 1000 miles home the next day (only touching the brakes SEVEN TIMES between Savannah and Pittsburgh... and not a single time in S.C.!!!)

A bugger to diagnose if you haven't seen it before. The easy fix is a new set of calipers. I chose new car instead... so I can't report that the issue was ever resolved!! I know now that the new car was the WRONG fix. I ended up getting rid of IT after two short years... because it had more problems NEW than the Stratus did at 100k....

Den

 

[awt28]

Thanks for all the help. I'm heading over to the sand box soon and when I get back I'm planning on replacing the calipers/pads, and bleeding the entire system. I'm thinking about having someone look at the drums since I never seem to get the darn things put back together quite right even with a diagram. I'm also hoping to fix a few extra problems that my XJ is having. Nothing major though.

Tony

 

[Beached Bones]

Wow, Thanks DenLip that's something I NEVER would have thought of. Seems to explain ALOT.

If only I could go back in time before the brakes seized orriginally, and just pitch the whole system and get a set of performance calipers/pads. Then I could have skipped the whole expensive repair bill, the headache and the possibility of it happening again.....

I'll take it easy on the brakes and see how it goes.... I drove 250 km today without the slightest trace of problem. All highway, very little braking.

Beached Bones

 

[Beached Bones]

Wow, Thanks DenLip that's something I NEVER would have thought of. Seems to explain ALOT.

If only I could go back in time before the brakes seized orriginally, and just pitch the whole system and get a set of performance calipers/pads. Then I could have skipped the whole expensive repair bill, the headache and the possibility of it happening again.....

I'll take it easy on the brakes and see how it goes.... I drove 250 km today without the slightest trace of problem. All highway, very little braking.

Beached Bones