brake smell


  #1  
Old 02-21-18, 08:56 AM
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brake smell

On the way to town this morning I got a distinct brake smell inside my jeep. Walking around the jeep I couldn't pinpoint the odor but the left front wheel and the right rear wheel were considerably warmer than the other two. Would this be a traction control problem?

2010 jeep jk
67k
no codes
 
  #2  
Old 02-21-18, 04:35 PM
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I think on that model they have a split MC The split is like you said. Possible 1/2 MC not working???
 
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Old 02-22-18, 02:19 AM
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I haven't had time to really look at it yet but intend to after I get back from the doctor this morning. I always thought that modern day master cylinders where split where one half was for the front and the other half for the rear ??
 
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Old 02-22-18, 02:50 AM
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Found this but can't seem to find out which system you have.
https://itstillruns.com/split-brakin...m-6545035.html
One site said front and rear are most common.
 
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Old 02-22-18, 03:40 AM
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Thanks, I had never heard of a diagonal split system before. I thought after they went to a split system it was always front versus rear. I've got a Haynes manual for my jeep - maybe it will shed more light.
 
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Old 02-22-18, 09:04 AM
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The diagonal split is common on cars but some still have front/back. It's specific to the vehicle.

Hard to say but simply spinning the wheels off the ground should quickly identify if a wheel is dragging!
 
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Old 02-22-18, 09:14 AM
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The front left wheel is definitely dragging! It takes effort to move it by hand and once the wheel is removed it's impossible to turn. I'm more confused than ever regarding the back. Both rear tires spin about the same BUT when you turn the right rear - it produces the distinct brake smell.

I'm thinking it might be a bad caliper on the front but I hate to replace parts without knowing for sure. Both front pads are close to needing replaced but the wear seems to be fairly uniform. My Haynes manual is for 198?-2011 jeep but it doesn't show a master cylinder set up like I have. 2 short brake lines connect the MC with an aluminum box that has 4 more lines going out to the 4 brakes. It also has an electrical plug, 1 to the MC and 1 to that box.
 
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Old 02-22-18, 12:47 PM
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Pretty easy to check if caliper stuck or brake line bad. Jack up wheel, pump brakes and if wheel won't turn crack the bleed screw. If wheel now turns brake hose is bad. If still stuck problem is with caliper.
 
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Old 02-22-18, 02:11 PM
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I cracked the bleeder and it didn't seem to help although I hadn't pumped the brakes. The tire was off so that made it harder to see if would turn. Still confused by the right rear wheel being hot yesterday and while it turns freely today it emits a brake odor.

Don't know if I'll have time to work on it tomorrow because we have to pick my wife's brother up at rehab. Doesn't make sense, they are sending him home with a knee cap that is continuing to separate and they will re operate tuesday - remove screws, add plate and new screws. Of course I'm sure he'd rather be at home than in rehab.
 
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Old 02-23-18, 10:03 AM
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If the caliper sticking you most likely need to replace it. It usually isn't a master cylinder problem usually the brake cylinder inside the caliper is frozen due to corrosion. Best bet is to replace that caliper with a new or re-manufactured one from your local parts store
 
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Old 02-23-18, 01:25 PM
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Start by ensuring the slider pins are free and well lubricated
 
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Old 02-23-18, 01:30 PM
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It might be next week before I can get back on it, things will be kind of busy around here the next several days.
 
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Old 02-24-18, 07:04 AM
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You have one line seized. reason they do diagonal is to prevent vehicle side to side skidding, as then you have brakes working on both sides and ends.
Either MC is bad, or line is clogged or bent. Seized caliper on one end will not produce the other caliper overheating. So it's something with brake fluid pressure inability to lower itself, resulting in high entire line pressure and dragging calipers. Surprisingly, it can be as simple as brake booster pin not retracting completely, causing slight pressure inside MC. been there.
 
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Old 02-24-18, 08:35 AM
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All the ones I've worked on [excluding the older single compartment MC] had the brakes split with one side of the MC for the front and the other for the back. I had never heard of a diagonal split before but then other than pads I've never worked on the brakes of something this new. Thanks for giving me something else to check into.
 
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Old 03-02-18, 01:14 PM
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I replaced the left front caliper and that seems to have fixed it although I've only drove it a few miles. Still at a loss as to why the right rear got hot .... and then seemingly fixed itself I will be keeping a close eye on it for awhile.
 
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Old 03-06-18, 08:20 AM
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Well I guess it isn't totally fixed yet Had to drive over to my BiL's apartment office to pay his rent. The brakes did fine going over there but on the way back it seemed like I had to use a lot of gas to keep rolling. Pulled into a parking lot and the right rear brake was steaming. I guess I'll replace that caliper too and see if that solves the brake issues.
 
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Old 03-06-18, 08:39 AM
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Are the calipers seized or just the slider pins ??
 
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Old 03-06-18, 09:07 AM
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The slider pins are free - still well greased from the factory.
 
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Old 03-06-18, 10:10 AM
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Still well greased from 2010 ?? ... I have seen them get sticky a lot sooner than that.
I have had them cause grief to the point where I lube them each year when I rotate the tires.

Good luck.
 
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Old 03-06-18, 01:19 PM
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I was surprised that they were still covered in grease and very free.
 
 

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