Alright this just started yesterday while out on a muddy trail and then continued intermittent the rest of the day. While even lightly applying the brake pedal the rear tires suddenly lock up and slide to a stop. This continued for the rest of the day around town and on my way home (a 90mi trip). I checked to see if any brake lines were crimped or the E-brake cable was jammed tight from a rock or unknown damage. All looks good however. It's weird and nerve racking, most of the time the brakes work fine, then all of a sudden, the rear tires are screeching to a halt. All I can really think of is the brake proportioner valve. Also the truck recently got out of the shop for gear swaps to 4.1 and a TrueTrac in the rear (Chrysler 8.25). However it was fine for the first couple of days, so not sure that it is something they did. I haven't yet pulled the drums do to lack of time but don't hear any bad noises so far. Thanks for any ideas.

 

My 01 did that the other day. Just did it for 2 stops. Been fine since. Maybe the parking brake wasn't disengaged? It's cold here in NJ, in my case I'm thinking/hoping the parking brake cables were temporarity frozen.

 

dirty brakes cold weather

 

mine does it anytime it rains or I go mudding etc. I've come to the conclusion drum brakes do not like moisture. Period.

 

Well I'm from Phoenix, AZ so I don't know that I would say that cold weather had much to do with it. I guess it could just have been mud/dirt, but I have been in much worse mud before and never had that happen. I am away for work right now, when I get back home I hope to have time to pull both drums and see what everything looks like, including the amount of pad left.

 

could be your self adjusters going bad or they are bad... it'll stick hard till you've pumped the breaks a few times right???? well after the brakes are "heated up" then the moisture will evaporate and good breaks again but then they get wet again and sticky sticky sticky... my rear drums need new self-adjusters lol have em but just not the motivation to install them in the cold weather

 

This happened to all my tires in my 89 limited it was the porpotioner valve it got clogged with red thick oily stuff so I unclogged it and problem solved

 

Drum brakes and water/ mud. When it happens i usually pull the drums and clean the brakes out with superclean and a wire brush

 

I can tell you exactly whats happening. My cousin had the same thing happen to his WRX after he upgraded his drive train from the tranny back. I was actually with him the second time it happened. The rear wheels locked up and it almost felt like his ABS kicked in. What was happening was his differential and tranny didn't quite have complimentary gear ratios, so every once in a while the rear diff would catch on itself and completely lock up. the abs kicked in because as soon as it happened he naturally pushed the brakes. The computer sensed brakes being pushed + rear wheels not spinning = activate abs. Hope this helps!

 

Do this: pull your tires and knock your drums off. Spray clean with brake cleaner(both drums and shoe areas). Wash the rim /tire clean. Reinstall tire. Check adjustment of emergency brake. If problem still persist flush brake fluid.

 

Mine would do that when they were extremely far out of adjustment.

 

Yeah! That's exactly whats happening on an XJ! LOL.

 

best bet is to open them up and have a look. I had that issue when I first got my jeep. turned out to be leaky wheel cylinder, and wet drums/shoes lock up. I also get it sometimes in the rain or cold, but not a lockup like I used to get. just biting earlier than the fronts, and it usually goes away by the time I get off my street.

 

that exactly was the problem with my 97 when it started doing that. had small leak on wheel cylinder. inside it was packed with moist brake dust. so i did both sides. new cylinders, shoes, springs and drums myself. was not even that expensive to do either. no problems since.

 

nice looking 2 door