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failed emissions... because I "don't have back brakes"

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Old Aug 21, 2012 | 04:42 PM
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From: foco, co
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Default failed emissions... because I "don't have back brakes"

Any thoughts on this one? I failed emissions today because they put it on the dyno and couldn't get the back brakes to stop the rear wheels. I have never worked with drum brakes in my life before and was wondering if I simply have to tighten something or if there's a bigger problem. I already did a visual inspection of my brake lines from the master cylinder all the way back and couldn't find anything wrong with them.
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Old Aug 21, 2012 | 04:47 PM
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Pull the rear tire. The drum's hat SHOULD slide off.

If it does, inspect the shoes, wheel cylinders, and adjuster. Replace as needed.

If not...then its prolly time to do some rear brake maintenance.
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Old Aug 21, 2012 | 04:52 PM
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Originally Posted by disguay
Any thoughts on this one? I failed emissions today because they put it on the dyno and couldn't get the back brakes to stop the rear wheels. I have never worked with drum brakes in my life before and was wondering if I simply have to tighten something or if there's a bigger problem. I already did a visual inspection of my brake lines from the master cylinder all the way back and couldn't find anything wrong with them.
Pull the tires off slide the drums off and see if there is anything left on the shoes. if not then replaced them. I would suggest buying the spring kit when you buy the new shoes. leave one side on and copy the other side if your not comfortable with doing the job. its scary at first but its a basic hand tool job.
If there is some brake left on the shoes then your self adjuster isnt working. that is at the bottom and is supposed to self adjust. If the adjuster can not spin then it will not self adjust. I would still suggest just putting new shoes on once you have the tires off and drums off. There are write ups out there to help you replace the drum brakes with pictures.
https://www.cherokeeforum.com/f51/ho...kes-d35-45100/
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Old Aug 21, 2012 | 06:01 PM
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Thank you to you both! I have done countless brake jobs, but I've always been scared of drum brakes because I've never had to dig into them before. I'll check into everything and I'll follow that write up and see if I can figure it out.
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Old Aug 21, 2012 | 06:06 PM
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Bad
failed emissions... because I "don't have back brakes"-misc20120817-016.jpg

Good
failed emissions... because I "don't have back brakes"-misc20120817-040.jpg
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Old Aug 21, 2012 | 07:47 PM
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I'm sure mine look more like the top picture, so I'll be getting parts for it here soon
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Old Aug 21, 2012 | 08:17 PM
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Why would it fail emissions because of rear brakes? It probably failed the safety inspection.
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Old Aug 21, 2012 | 08:23 PM
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Splitting hairs at this point. All that really matters...rear brakes dont work and need to.
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Old Aug 21, 2012 | 08:53 PM
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Originally Posted by Kalali
Why would it fail emissions because of rear brakes? It probably failed the safety inspection.
When doing emission testing on a dyno, you need to be able to brake when your finished. Also some states do a loaded emission test by dragging the brake a little while accelerating the vehicle to simulate actual driving conditions.
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Old Aug 21, 2012 | 09:01 PM
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Originally Posted by Willys55
When doing emission testing on a dyno, you need to be able to brake when your finished. Also some states do a loaded emission test by dragging the brake a little while accelerating the vehicle to simulate actual driving conditions.
Who sits on their brakes while accelerating in real life??
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Old Aug 21, 2012 | 11:48 PM
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We have dyno emissions and they told me it was unsafe doing a rwd dyno without rear brakes. I told them I could put it in 4wd, and we could put it on an awd dyno and use the front brakes to stop the rear wheels and they said they had already associated my VIN with needing a safety inspection prior to testing so they can't do that. I'm guessing they will find something else if they do a safety inspection...
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Old Aug 22, 2012 | 06:24 AM
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Originally Posted by disguay
We have dyno emissions and they told me it was unsafe doing a rwd dyno without rear brakes. I told them I could put it in 4wd, and we could put it on an awd dyno and use the front brakes to stop the rear wheels and they said they had already associated my VIN with needing a safety inspection prior to testing so they can't do that. I'm guessing they will find something else if they do a safety inspection...
Inspect and adjust if possible. The "self adjusting" brakes on our Jeeps don't.
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Old Aug 22, 2012 | 07:06 AM
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Originally Posted by cruiser54

Inspect and adjust if possible. The "self adjusting" brakes on our Jeeps don't.
A PO actually took all the self adjusting stuff off my drums. They aren't even pretending to be self adjusting anymore, lol!
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Old Aug 22, 2012 | 09:44 AM
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Originally Posted by cookrw
A PO actually took all the self adjusting stuff off my drums. They aren't even pretending to be self adjusting anymore, lol!
Sounds safe.
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Old Aug 22, 2012 | 05:36 PM
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So I pulled off everything and it looks like my shoes are fine. How would I go about "adjusting" the brakes?
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