Preventing Brake Drum Overheating: Why Regular Temperature Checks Matter

[MtnGuy]

I have put about 4200 miles on my Imagine XLS 22MLE since we bought it in May 2024. I check the hubs with an infrared gun at most stops. From the get-go, the front curb side drum ran hotter than the other 3 drums. I contributed it to the self adjusters just kicking over quicker than the other hubs. On a recent trip stopping at a rest stop on the interstate, 3 of my drums were around 150 degrees F, and the curb side front was at 250 degrees F !!

I took the camper to my local RV shop, and this is what he found:

I realize now that I should have looked into it right away, but again it might not have been evident with just a few miles on the trailer.

All other shoes looked great, as well as my bearings. He replaced the faulty shoes with a manual adjusting setup. When the time comes for the other 3 replacement shoe sets, I will also be installing manually adjusting units.

Did I mention that I do not like self adjusting brakes on trailers ?? Crawling under the trailer once or twice a year to adjust the brakes is no big deal.

 

[GaryMGg]

Looks like you got ahead of a potential hazard. Great work. The guys I know who have been “coaching” me say check the drums every time you get out of the TV. If it’s hot to the touch, it’s probably not good.

 

[el Rojo]

Did they say what caused the failure?

 

[MtnGuy]

Did they say what caused the failure?

It was never stated directly. I imagine that the heat from the constant rubbing was the cause, but that was just my opinion. He could have just installed new shoes on the old system, but he thought the automatic adjusting on that particular brake unit would just tighten up too much again. There is apparently no easy way to “adjust” the self adjusting brakes.

 

[Scott'n'Wendy]

I don't remember self adjusters on our 2021 303.
Glad you got it corrected before you were sitting on the side of the road with a melted down hub

 

[MtnGuy]

I don't remember self adjusters on our 2021 303.
Glad you got it corrected before you were sitting on the side of the road with a melted down hub

I had the self adjusters on our 2017 337RLS, but never had a problem with those.

Those hubs ran about the same temperature all of the time.

 

[dryfly]

All other shoes looked great, as well as my bearings. He replaced the faulty shoes with a manual adjusting setup. When the time comes for the other 3 replacement shoe sets, I will also be installing manually adjusting units.

Have you checked out modifying the self-adjusting assembly to a manual adjusting assembly? I'm thinking I've read it's possible.

 

[MtnGuy]

Have you checked out modifying the self-adjusting assembly to a manual adjusting assembly? I'm thinking I've read it's possible.

Yes, that was done.

I asked about just replacing the whole assembly including the backing plate to a manual system. With the anti lock braking system, there is a sensor on the backing plate, so no go with that.

 

[dryfly]

Yes, that was done.

I asked about just replacing the whole assembly including the backing plate to a manual system. With the anti lock braking system, there is a sensor on the backing plate, so no go with that.

I did not think about that. My trailer was built before the anti-lock systems started being used. On the old assemblies I think all you have to do is remove the self-adjusting lever and you are good to go.

 

[MtnGuy]

I did not think about that. My trailer was built before the anti-lock systems started being used. On the old assemblies I think all you have to do is remove the self-adjusting lever and you are good to go.

That is probably what was done to mine.

 

[Riverbug]

Good catch! It pays to pay attention to those details (giving everything a quick look at each stop).

 

[el Rojo]

This thread is a great PSA for the newer RVers. I too check hub temperature every time I stop the RV. You can see a problem coming before before you're stuck on the side of the road with the wife, kids and dogs standing in the ditch.

What I look for is temps to be within 10% of each other on the same side of the rig. Each side of the rig will be different because of sun or road crown. The hottest I have seen is 147 degree average on a very hot Texas afternoon. And that was after going through several stop lights. My average temp is 105 to 125. I usually find the wheel closest to the frig a little hotter which I attribute to the extra weight.

Hope this helps our readers.

 

[RV2600RB]

Looks like you got ahead of a potential hazard. Great work. The guys I know who have been “coaching” me say check the drums every time you get out of the TV. If it’s hot to the touch, it’s probably not good.

That’s what I do at gas stops. Using the back of my hand.

 

[jleonard]

That’s what I do at gas stops. Using the back of my hand.

I also use the back of my hand during pit stops. If any were hot Id break out the temp gun, but have not had to do that yet.

 

[Steven@147]

Very good advice. At each stop do a walk around your RV and check the tires also check for even heat.

Last year we were traveling and I noticed on our RV TPMS the right front non-ABS RV tire air temp was going up well beyond the others. Understand with a stuck brake, heat has to transfer from the brake drum to the wheel rim and then heat up the air in the tire enough for you to notice it on your RV TPMS.
By the time I got off the road and into to a Buc-ee's parking lot, I shot the rim with my temp gun, the wheel rim was well over 200

Short story the right front brake assembly had come apart and pieces got stuck in there and jammed the brake on. I carry two complete spare non-ABS RV brake assembly backing plates, one right and one left. R&R 5 nuts and connect two wires - done in @ 30-40 min.
I did have to get a new drum and replaced it later after getting to our destination and receiving a new drum.

ABS Drums- Yes the RVs with drum brake ABS have specific brake assemblies. Brake backing plate with wheel speed sensor and a different brake drum with slots cut in it acting as a reluctance ring.
I have never had a good look at one but I believe the wheel speed sensor is removable from the backing plate, so if you had a complete spare ABS brake backing plate, you could remove the sensor from the original, bolt on the new backing plate, re-install the sensor to get you to your destination. Then adjust the brakes, it will get you out of a brake down on the road