Why are these rear brakes grabbing and locking??

[longcruise]

Found this forum on Google and it looks like the right place to find answers about these vehicles. This is my first post and I may not be as mechanically adept as some of you folks so please bear with my terminology and so forth! (also my typing since my hands are frozen and I've spoent the last 5 hours blowing snow! )

So, here is my problem. My rear brakes on my 1992 Navajo will engage all by themselves. I must confess that this probelem did not just crop up anew today and I've been sort of aware of it for a while! It was really noticeable today because we just had a pretty good blizzard and I was driving on a snowpacked street this morning and the rear brakes did their "thing". The wheel that was not providing power just stopped turning and and dragged immobile across the snow. Even though the 4X4 was engaged, it caused the vehicle to slide into a spin.

Previoulsly the rear would grab intermittently while driving in 4X4 or 4x2 mode. I even felt this happening once on the interstate at speeds of 55 or so! Without a slippery surface beneath, it's just a sudden grab and release but today on snowpack it locked and stayed locked on the right rear wheel.

Here are some other observations; this seems to happen mostly when the weather is cold. If I set the parking brake during cold weather, the rear brakes seem to be locked when first moving the car (not talking frozen mosture hear cause it can happen at 40 or 45 degrees farenheit). The most disconcerting thing though is the way they just grab and let go while driving (and not let go when on a slippery surface!).

The car has rear abs and I thought it might be related to that, but don't know for sure. I tried to remove the abs fuse but without an owners manual I can't tell which one it is .

If you have any ideas on this, sure would like to hear them!!

Longcruise

 

[LXNavajo_94]

Sounds like a broken or weak return spring but I could be wrong. When was the last time you had any work done on the rear brakes ? I have also seen this happen when the lining breaks loose and intermittently grabs before releasing . I guess your best bet would be to pull the rear wheel and drum and see whats going on inside. Some of the other regulars might have a better answer for you . Welcome to the forum there's lots of good help to be found here. Also when in doubt do a search there might be an answer to some of your questions there.

 

[makdgto]

My 94 x was doing the same thing I found that the axel seal had let go oil all over the shoes. Then when it got cold the oil became paste and locked up that wheel. good luck. mike

 

[mrboyle]

Sounds like a leaking axle seal to me also. Just FYI, be prepared to replace the axle shaft when it comes time to repair/replace the seal. It is not uncommon for this type of axle shaft to wear a groove in the bearing surface which causes the leak in the first place. Unless it is a absolute necessity, DO NOT use one of the off set "repair" bearings. They are a temp fix at best and will only delay the need to properly replace the axle shaft.

 

[marragtop]

If it is the axel seal, you should see signs of leakage on the backing plate. You need to pull the drum(s) regardless.

 

[4dexplorerowner]

Dilemma. My 94 explorer 4x4 sat at mother in laws for 2 months while I used her second car for long trips. Anyway, after going there to take it home, the car would not move when shifted to drive, but would reverse. I used moms car to push it and noticed that the back driver side wheel was not rolling. Any thoughts?

 

[safn1949]

Dilemma. My 94 explorer 4x4 sat at mother in laws for 2 months while I used her second car for long trips. Anyway, after going there to take it home, the car would not move when shifted to drive, but would reverse. I used moms car to push it and noticed that the back driver side wheel was not rolling. Any thoughts?

Did you have the emergency brake on? It sounds like an E brake cable froze up and won't release..

 

[LAWG_rider]

I had this same problem. Then one day it stopped magically. Then my brakes REALLY started grabbing. When I took the drum off I found that the parking brake cable had not just seized but was completely torn off and just floating around in the drum. The real grabbing started when it would get between the drum and the shoe.

 

[runderwo]

Old brake hoses can collapse and prevent fluid from returning too.