One very hot brake drum, one cold

Nessmuk

Just got back from our first trip with our new 2021 320S Boondock. I checked hubs and drums for excessive heat along the way. I also adjusted the brakes. On the way home today I discovered that the driver side drum was quite hot while the other side was cold. I pulled into a shopping center and backed off the brake shoes a bit more. Still way too hot when we arrived home. Too hot to touch, but cooled down quickly.

Anyone else have a similar issue? I will look at the bearings, but find it hard to believe Dexter or NuCamp would ship an axel that was improperly lubed.

manyman297

So I had a similar issue on our 400. Passenger was running really hot (could smell burning brakes). It took a few trial and error runs but I finally backed off the brake enough to fix the issue and now both drums are fine (running nearly the same temps checked using a thermal gun). 

Do you smell burning brakes?

Nessmuk

I did, that is what made me check them when I was stopped for gas. It wasn’t overpowering, but enough that I noticed while walking around it.
It is going to be put up for the winter so I will have to pull the drums and check out the pads and bearings.

Michigan_Mike

I had the same issue early on with my 400.  I backed off the pressure on the brake controller and this resolved the issue.  I do check the heat on the bearings when I’m traveling across country and I have not had any additional issues since I made the adjustment on my brake controller.  

Dutch061

Also for kicks you can check the amperage draw. If you have a BMV-712 or a clamp on meter (or similar) and pull the emergency stop plunger you should see around 6.2 Amps for the pair of magnets. This will quickly tell you if you have 1 side that is not working.

As @Michigan_Mike said, trailer brake settings are one of the keys to long and happy brakes. Some people tend to rest their foot on the brake pedal too, not enough to apply the TV brakes but it certainly applies the trailer brakes. Using the trailer brakes to stop the TV is not good 

Brad

Nessmuk

I am going to check all the wires and readjust the brakes on both sides. If that doesn't clear up the problem I will check with NuCamp and my dealer. It’s only a few months old.

peterjoce400

Very same issue:  driver's side running hot on brake ( not hub or bearings).  Shop couldn't find anything wrong but replaced brakes and also the brake controller.  Will see if beneficial in spring.  Old brakes were still fully serviceable with 8,000 km on them but now with new brakes both sides it takes the elimination down to purely electrical.  TaB400 2019 (built 07/2018)

manyman297

I would really suggest playing with the drum brake adjustment first. In most cases it’s usually just a dragging drum which is what I had. Even after adjusting the passenger side to the suggested point where you feel a little bit of drag I still had to let even more off that side to eliminate the heat issue. It’s been fine most of the summer/fall.

And do as @Dutch061 suggests as well since that rules out any major electrical issues.

Nessmuk

Well I finally got around to checking the “cold side” and it took quite a bit of turning the star wheel to get the shoes to grab the drum. I backed it off to match the other side so come Tuesday I will see if that was it. Taking it one hour away to the dealer to let them take a look after they winterize it. I was going to winterize myself, but figured let them do it this year since I want them to check the brakes should the problem persist.

rh5555

Another reason for a brake running hot is a broken return spring.  You'll need to take the hub off to see if that is the problem.

warbler_road

My thread from 2020 describes my similar problem -- it was the cool side with the problem. Grease had been pushed out of the EZ Lube bearing, fouling the shoes and drum, and the opposite brake was still doing its thing and overheating. Open up the brake drum of the cool side and see if you have grease in there.

Nessmuk

I will take the drums off. I just got back from the dealership and they put the test box on the trailer and both brakes worked as they should. This is a real head scratcher. I adjusted both sides yesterday before I took it in. 

Can a brake controller cause this sort of problem? There is only one wire to deal with so shouldn’t both sides be getting equal current?
When I arrived at the dealer the left side drum was 175° and the right was 67°.
The odd thing is it doesn’t appear to be pulling to one side when braking.

Denny16

You can not adequately check the brakes with a test box.  That only tells you the brake solenoids are working, not necessarily the brakes.  You need to pull,the drums and physically inspect the brakes.  I get this done annually, every spring at a local trailer repair shop.  As pointed out here, you could have grease in the drums, bad brake shoes, broken springs, etc causing braking issues.
cheers

Nessmuk

I will just take it back over the winter. Since it has lots of warranty left I will let them figure it out. I will pull the drum this weekend though to see if it is something obvious.