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Astroinfidel
03-09-2018, 04:53 PM
Hi everyone,

I recently had the brake shoes replaced on my Everest, and since then they have been running really hot, even on the highway with no use of the brakes. Obviously sounds like they are adjusted too tight, right? Nope. I've spent the last two days at the shop that installed the shoes, and they have torn it apart twice looking for the problem. They adjusted them so loose I hardly had any trailer brakes at all, and they still got hot on the highway. If I am on just the smallest slope, the truck and trailer will roll from a standing stop, so I have no sense that the brakes are dragging. When the brakes were adjusted by the shop, they adjusted them so that a good spin of the tire would continue for three rotations. That doesn't seem too tight to me.

Today I replaced the stock brake controller in the 2017 Ram 3500 with a Prodigy 3. I wanted to replace it anyway, as the stock one does not provide nearly enough braking power, even turned up to 10 on the gain. I just came back from a test drive with the new controller, and while the brakes are definitely more powerful than with the stock controller, they are still running hot for no reason. The Prodigy screen showed zero volts being sent to the brakes while on the highway, so I don't think any electric charge is somehow bleeding to the brakes while driving. The brake temps were 250-300F after a 20 minute drive, mostly on the highway, with light braking only. if I understand correctly, they should be more like 130 - 150 after a drive like that.

On Monday, I will replace all four brake assemblies with new ones - everything from the shoes to the magnets to the backing plate will be new. I am new to electric brakes, and find this kind of frustrating, and expensive. I have a 3000 mile drive coming up in a week, and I have to get this sorted out before i leave.

Any ideas as to what could cause brakes to run hot while showing no indications of dragging would be much appreciated.

Dean

jsmith948
03-09-2018, 05:25 PM
Hi everyone,

I recently had the brake shoes replaced on my Everest, and since then they have been running really hot, even on the highway with no use of the brakes. Obviously sounds like they are adjusted too tight, right? Nope. I've spent the last two days at the shop that installed the shoes, and they have torn it apart twice looking for the problem. They adjusted them so loose I hardly had any trailer brakes at all, and they still got hot on the highway. If I am on just the smallest slope, the truck and trailer will roll from a standing stop, so I have no sense that the brakes are dragging. When the brakes were adjusted by the shop, they adjusted them so that a good spin of the tire would continue for three rotations. That doesn't seem too tight to me.

Today I replaced the stock brake controller in the 2017 Ram 3500 with a Prodigy 3. I wanted to replace it anyway, as the stock one does not provide nearly enough braking power, even turned up to 10 on the gain. I just came back from a test drive with the new controller, and while the brakes are definitely more powerful than with the stock controller, they are still running hot for no reason. The Prodigy screen showed zero volts being sent to the brakes while on the highway, so I don't think any electric charge is somehow bleeding to the brakes while driving. The brake temps were 250-300F after a 20 minute drive, mostly on the highway, with light braking only. if I understand correctly, they should be more like 130 - 150 after a drive like that.

On Monday, I will replace all four brake assemblies with new ones - everything from the shoes to the magnets to the backing plate will be new. I am new to electric brakes, and find this kind of frustrating, and expensive. I have a 3000 mile drive coming up in a week, and I have to get this sorted out before i leave.

Any ideas as to what could cause brakes to run hot while showing no indications of dragging would be much appreciated.

DeanIf the new shoes are the proper width, the only way they can create heat is if they are adjusted too tight or the brakes are being partially applied.

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BigTexRex
03-09-2018, 05:28 PM
I've always heard, and what I do, if the brake shoes are worn replace the whole brake assembly. They are not any more expensive and replacing just the pads and much easier.

slow
03-09-2018, 05:28 PM
May not be the brakes, but rather the preload of the bearings may be the problem.


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jsmith948
03-09-2018, 05:30 PM
May not be the brakes, but rather the preload of the bearings may be to the problem.


Sent from my iPhone using TapatalkTotally agree.

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sourdough
03-09-2018, 05:32 PM
I'm thinking slow might have a thought. How are you judging that the BRAKE PADS are getting hot? Or, is the wheel hot? Or? With all you've done and checked I have a hard time thinking that the brake shoes are causing the issue.

chuckster57
03-09-2018, 05:37 PM
May not be the brakes, but rather the preload of the bearings may be to the problem.





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Sort of what I’m leaning towards. Take the center (hub) cover off the wheels. Then use a laser temp on the spindles and drum after driving. I would think the spindle would be a lot hotter.

Astroinfidel
03-09-2018, 07:22 PM
Thanks everybody. The shop I am at specializes in RVs and has a good rep, so I'd be surprised if they are tightening the bearings too much. They just repacked them for me as well. But I will bring up the possibility to them. So far I have been taking the temps of the same location on the drums - right at the edge of the drum that faces me as I look at the wheel, as far from the spindle as possible. Right before the face of the casting ends and "turns the corner". This is the easiest place to reach. I measure about 1/2 inch in from the very edge. If there is a better place on the drum to measure the temps, I would of course like to know. I am using an IR sensor, and I am seeing temps between 250 -300F at that point on the drums with light use. And the smell is very hot, and the heat radiates quite a distance from the wheel.
And chuckster, the idea of seeing which is hotter, the drum or spindle, in order to see where the heat is coming from is a great idea. I will do that on Monday with the mechanics present, and that should point us either towards or away from the bearings as the problem. As hard as it is to believe the mechanics here (I am still in my Everest on their lot for the weekend) would be making such a mistake, it sure does seem to be the most logical reason for the overheating.

Thanks for the suggestions everyone. I am quite a bit more optimistic than I was before hearing them!

Dean

Hideout17
03-09-2018, 09:06 PM
Sounds like both ideas I had have been covered. One way to check to see if it the electric brake issue is to disconnect electric brakes on trailer and drive, if it can be done safely. Even a short 10 mile stretch could help. Check with and without electric on. May be possible, outside chance, brakes are getting power from somewhere else, short.
?

flybouy
03-10-2018, 03:52 AM
I don't know what a " good spin " is but if the wheels will rotate 3 times after spinning I would think the bearing preload shouldn't be the culprit but it's something to check. There are only a few possibilities here. Your brakes were replaced so in my thinking there are 2 probable causes. Either the brake shoes are dragging or the bearings have excessive preload. I would suspect improperly sized or defective brake shoes or improper install where the shoes are not retracting.

Dave W
03-10-2018, 05:43 AM
Have you checked the breakaway switch. These are really pretty cheaply made (10-12 bucks) and occasionally fail. The pin may also be partially pulled too though that's a stretch

Also check the wiring as 'stray' voltage to the brake circuit from either the RVs wiring or TV may be activating the brake magnets - this to be done with your TV hooked up to the pigtail, not the shop's TV.

Ken / Claudia
03-10-2018, 10:36 AM
I do not know what is a correct temp of the brakes, but a standard would be what was the temps before the shoe change. If it was me having this problem I would first adjust the brakes as was done, the next step would be to make sure the drums are not the problem as in out of round etc. double check the shoes are drums are the right ones. I would think the shop already did that but, it was not mentioned. Did the shop say the temps you have are to hot.
In the last 8 years I had new drums on 2 different vehicles that were out of round. Before I got a new break controller I would have the trailer system 100% sure it is not the problem.

FlyingAroundRV
03-10-2018, 12:29 PM
I'm going with an electrical fault. If you have access to a volt meter, the first thing to try is to check that what is coming out of the socket on the TV is what the standard wiring diagrams say it should be. If that all looks good, try hitching up the trailer and connecting the electrics to the TV. Chock the trailer wheels and start the truck engine and turn on the parking lights. Then jack up one wheel and pull the drum off. Then measure at the brake magnet to see if you have any voltage appearing there. get someone to apply the truck brakes and see whether any voltage appears at the magnet.
If only one brake is getting hot, I'd suspect a mechanical issue. If all the brakes are hot it may still be mechanical, or it may be electrical.

notanlines
03-10-2018, 06:25 PM
I'm going with the electrical side of this. Years as an auto/truck mechanic back in the day lead me away from the wrong preload. Not exactly an evil idea, but the odds of all four wheels rule that out.

gearhead
03-10-2018, 06:28 PM
If you feel OK doing it, I would try to drive it either using the brakes as little as possible or the controller turned all the way down, as a previous poster said. Maybe 5-10 miles and then check the temps. Compare the temps on the outer edge of the drum to as far in as you can for the bearings.
I had all kinds of brake issues. Had 2 shops adjust them with no results. One in Indianapolis and one in Houston. I drove to Indy and back with 1 brake. I ordered new self adjusting brakes, complete with backing plate and magnets from eTrailer. I did the electrical connections with waterproof butt connectors with heat shrink over that. Doing great so far. Went from running "7" on the controller to "4".
I bet the magnets are shot and you need to start over with at least new magnets.
Did you break in the new shoes?
Please let us know how it ends.