Wrangler Rear Brakes

Drum brakes are easy, but if you mix up the star wheels you can fix the automatic self-adjusters so that they automatically loosen the shoes instead of tightening them. That is not a good thing. I would say yes to the hardware; it's only $15. If the adjusters have been working then the shoes will be right up against the drums and this will make the drums hard to get off. Then you have to crawl under there and figure out which way to turn the star wheel to get the shoes loose. Most people turn them the wrong way first. Result, drums and shoes locked together. It is recommended to turn the drums every shoe replacement, but some people don't, particularly if they are not too worn. They can be out of round though.

Once you get the drums off, take pictures with a digital camera. In the old days, we had to remember stuff like that. There is a difference between the "leading" and "trailing" brake shoes. If you mix them up you will get reduced service life out of them.

In Colorado this time of year you can work on a car outside for maybe three hours during the "hottest" part of the day, if the sun comes out, more if you are desperate. In an unheated garage in the Northeast? I have done that.

Cheers,

Earle

Too many dead links. Clean them up.

Thanks Earle. I am thinking that perhaps the adjusters might not be working and thus the braking differential? When I asked for the fixing price quote the guy said to me that it might only need adjusting and maybe not the whole replacement thing. He has seen 150K on rear brakes on TJs.

The digital camera thing is spot on. I did that with the front brakes and it helped.

I am in NJ, so it is pretty cold here now. I plan to drive the Jeep into the double garage on an angle taking up both bays and run a couple of heaters. Tomes

"Earle Horton" ...

Thanks Bill, nice to talk to you again. I am thinking that I am fixing to do what you say prety much. What are these 'cups' of which you speak? Tomes

I don't know what you mean by "braking differential" or "braking difference". An inspection shop can measure pad or shoe thickness, but you don't have to replace them until you get down to the minimum. I don't know how they would tell that the rears aren't working as well as the fronts. I agree with the assessment that they might only need adjusting. On a front disk rear drum setup the proportioning valve gives that much more pressure to the fronts, and the greater surface area of the rears means that they do indeed "last forever" compared to the fronts.

Cheers,

Earle

In the NJ inspection they run the vehicle over a 4-piece grid and slam on the brakes. Each piece is under one wheel. It somehow measures the braking force on each wheel separately. So it concluded that my front brakes are doing a too high percentage of the braking force. In NJ we go to a state inspection lane where they have a series of tests that the car rolls through, all computerized and administered by Parsons Inc or somesuch. It is a free service run by our taxes; we alternatively can go to a garage, but they charge a lot of cash for an inspection, so everyone goes to the state one. Emissions, for example, are done by plugging into the computer and having it say that all is well, not by the sniffer anymore unless the car is too old.

I think what I am oging to do first is put it on jackstands and see if adjusting adjusts anything (if the adjuster moves at all) if it does I would then just go run it through the inspection again to see if it works. My second thoughts were since I have it up I might as well take off the drum and have a lookey at it. Then if I have a lookey, I might as well change them out. Sheesh.

I think I am talking myself into just doing it... Tomes

Point taken, but I am thinking that I am still going to do it as I know I will eventually be OK at it. You have any links to a play-by-play through the rear brake job? Tomes

If your emergency brake is working and feels in the right place, you back brakes are properly adjusted. If the e-brake is right at the end of it's play, then it needs adjusting or more likely new shoes if the adjusters were working properly.

Mike

Thanks Mike, good talking to you again. The E-brake works normally. I am fixing to go get the stuff to do the brakes all in one go. Do you have a link to a step by step how-to for this? I just do not want to miss anything as it has been a bunch of years since I have done this. Thanks. Tomes

"Mike Romain" ...

Bill's PDF is a good one.

The brakes aren't hard, the springs are a pain to get off. I use needle nosed vise grips to grab them. There is a neat spring removal tool at auto parts stores.

Some brake backing plates have two grommets, one for adjusting, one for inspecting, I don't know TJ ones though.

Mike

Tomes wrote:

Wow, here in Colorado we don't have safety inspections and I get out of emissions inspection by not being in the "Clean Air Program" area. There are far fewer unsafe-looking rust buckets on the streets than one would expect. I remember tweaking cars so they would pass Massachusettes safety inspection. It was easy, but the fixes rarely lasted more than a week. That is some serious Nazi shit you have in New Jersey, and I was thinking of moving back to the East Coast because I am getting older and they have more "culture" back there. Joe down the street is ninety-four and if Colorado is good enough for him it is good enough for me.

Unless your rear shoes have something on them or are glazed (possible?) then an out of adjustment condition will just make them engage slighty later than the fronts. In practice this won't hurt your braking at all, because we are only talking fraction of a second here, less in a panic stop situation. But if adjusting them makes your inspectors happy then go for it. Another possibility is your proportioning valve. This balances the pressure between the front and back brake systems. If it is out of whack then loss of rear braking force is a distinct possibility. If the shoes look glazed then sanding them might help, but you might have to get new shoes and turn the drums just to pass the safety test.

Cheers,

Earle

Thanks Bill, much appreciated. Tomes

Needle nosed vice grips I have and will deploy. Thanks! Tomes

I never knew the proportioning valve could be adjusted. I thought it just was what it was. I do not believe I will be messing with that on this, yet thanks for the explanation.

I have lived here in NJ all of my life and the inspection station thing has been around longer than the 50 years I have been around. It is just baseline for me. I think it is a reasonable enough checkpoint for finding something dastardly wrong that i might never know about, and that balances out the nit picky stuff like a cracked turn signal lens. It can be annoying when something like what I just failed for on my Sienna happens - the heating element on the O2 sensor in the exhaust causes a code that the inspection picks up and fails for. All that does is warm up the sensor faster in the winter so the car leans out quicker and puts out marginally less pollution. Marginally, from what I understand. So I have just been running it with the check engine light on and checking the codes once in a while to be sure that no new code has popped up. Now that failed the inspection for that so I gotta buy the $120 part and put it in. I likely never would have fixed that, but now i must. That's my other job to do in the cold.

Tomes

I am not saying it can be adjusted, as I don't really know, but it can certainly be bad. If you put new or known good shoes in there, adjusted properly, then the proportioning valve could at least be something to think about, as could the master cylinder. If you haven't done this already, then flushing the brake fluid won't hurt. If you think the brakes are OK, and they fail the test, it sounds like a marginal thing as you say.

Cheers,

Earle