Rear Brakes Seized Up!

[madbrown]

I've got a 98' XLT Explorer on which the back brakes appeared to have seized up. Been smelling something burning off and on for some time and couldn't figure out the source. Then the other day I was pulling a trailer up the driveway and I completely bogged down. Initially thought I had a flat so got out and checked, and everything was good. Got back it and gave it some gas and it didn't move. Tried it again, and started cruising along like nothing was wrong. The following day was running some errands, and upon putting it in "drive" the rear driver side brake was squealing. After the short drive home I pulled the rear driver side wheel to have a look. I really don't know much about the innards of brakes, but the pad seems to be locked onto the rotor. The rotor and the caliper (I'm guessing) are probably still stock as they are quite rusty. Anyways, which avenues should I look at to get it unstuck? Like I said I'm not brake savvy, but have checked fluid which level is good, and looked at master cylinder, which exteriorly looks new/fine. Was wondering if I release the rear bleed valve on the brake will that release the caliper, and if so would it affect the front brakes as well. Sorry for the long post, but I appreciate any advice/help. Thanks

 

[JCat]

What happens when you jack-up the rear, put the tranny in neutral, and try to spin the tire ?

 

[madbrown]

Got the other side jacked up as well, and put it in neutral, anf the tires do not spin

 

[jremington59]

If it's locked up and rusty you need to put a new caliper on it. Next time you feel the sticking just touch the rims and you'll know which one it is. Just brush your hand across them because the one sticking will probably be hot enough to burn your hand.... I'd advise not driving them like that very far. They can get hot enough to start grease burning.

 

[madbrown]

Yep that's what happened when I touched it. The problem is I can't get it unstuck. Would like to drive it to the mechanic as changing the caliper is over my head?

 

[jremington59]

If you look at the caliper you will see a rubber boot that covers the slide that the caliper slides in and out on. Try spraying inside that boot and tap it with a hammer and see if you can get it to back off. Also look at the rubber line that connect to the caliper and make sure that hasn't collapsed. Believe it or not, if you buy a loaded caliper you can chage it in just a few minutes. Make sure that you spray the nut where it connects to the caliper so you don't twist it off.


Don't take the caliper off to drive it because when you hit the brakes it will push the piston out of the sleeve and you'll lose all the fluid. Do you have triple A? If so have them tow it to the shop for you.

 

[madbrown]

For spraying, would something like WD40 be alright? And what should I tap, the "slide"? Thanks again. I appreciate the advice.

 

[jremington59]

PBBlaster works well. And just wack the top of the caliper a few times and see if it backs off.

 

[madbrown]

Heading to town today, with another rig of course, I'll grab a can and give it a shot. Thanks again.

 

[bluestream1]

Could be parking brake actuator seized. Have you applied the P brake recently?

 

[madbrown]

I have, but the parking brake engages and disengages. How are you able to determine if the actuator has seized?

 

[bluestream1]

You need to look at where the cable pull on the lever right behind the brake plate. The foot petal can move, but the brakes can be seized. Easier to do with the wheel off. Have someone engage the P brake and watch to see if it moves and release. If it is stuck on, you can hit it with a hammer and it should disengage. These are notorious for seizing up.

 

[madbrown]

Sorry, but where do I locate the brake plate? and do mean the front driver side wheel?

 

[madbrown]

Figured it out. The parking brake appears to be engaging and disengaging properly. The pads are still locked onto the rotor.

 

[madbrown]

Tried pb blaster on the slides, as mentioned above, and still won't budge. Wondering if I cracked the bleed valve slightly won't that back off the pressure on the caliper?

 

[bluestream1]

I don't think that will help if they are seized. Did you try unbolting the calipers? They are a 10mm I believe. If you can get those 2 bolts off, you should be able to tap off the caliper with a hammer. Or pry them off with a crow bar.

 

[jremington59]

You can try it. It's not going to hurt anything. Just don't press down and release the brake pedal with it loose. But it sounds to me like the caliper is seized.

If you go and buy a caliper with the pad already installed in it (a loaded caliper) we can walk you through changing it if you have the right size socket.

 

[madbrown]

I just got the rear driver side caliper off. The rotor and pads appear to be in good shape, no grooves or gauging that I can feel and there looks to be a good amount of meat on both pads. Now just wondering what to do. Should I clean the piston w/ pb blaster and work the piston in and out with a clamp to loosent it up? Also, just wondering how much space should there be between the pads and rotor anyways?

 

[bluestream1]

you can try to work it loose, but you likely have to rebuild it, or buy rebuilt calipers. The pads will actually rub lightly against the rotor in normal use; there is no clearance to speak of

 

[jremington59]

You don't want to press the brake with the caliper off or you'll have the piston out. If you have a large pair of pliers or the right clamp you can press it in a ways and lubricate it. You might better spend the 50 bucks and get a new caliper though. Did you make sure the rubber hose connected to the caliper hasn't collapsed?