Curt ABS brakes on new Solitudes

[Hoopy Frood]

I just returned home from a trip with my 346FLSR and had a catastrophic failure on 2 of the 4 brakes. The other 2 need 2 new pads the other 2 are completely shot...drums, hardware and shoes. My dealer has jumped right in along with GD and Curt. I actually had no idea that it had ABS. Has anyone else have a failure like this?

Could you describe what the catastrophic failure was? Wheel came off? Brakes failed and locked up? Caught fire? Both on the same axle/same side? Did you get an explanation of how the ABS works with the drum brakes? Or are these disk brakes? Never mind, missed the drums first time around.

[CharlieP]

This is a new rig with only about 500 miles on it before this trip. I have a 2022 GMC 3500 dual wheels pulling/stopping it. The "catastrophic failure" was described by GD and Curt. The front Drivers side was a total mess. Drum destroyed, break shoes gone along with all of the parts and what was left was grinding against the drum. Passenger side rear same thing but not as bad. So both of those breaks were not working at all. Passenger front left and driver side right shoes were burned down almost to where they meet the drum.

Lucky to get home. I have TPMS and heat sensors and nothing was out of line.


I find it peculiar that the destruction or failures were diagonal from each other.

I hope to get an explanation on how the electronic ABS works from both GD and Curt.

[Hoopy Frood]

This is a new rig with only about 500 miles on it before this trip. I have a 2022 GMC 3500 dual wheels pulling/stopping it. The "catastrophic failure" was described by GD and Curt. The front Drivers side was a total mess. Drum destroyed, break shoes gone along with all of the parts and what was left was grinding against the drum. So both of those breaks were not working at all. Passenger side rear same thing but not as bad. Passenger front left and driver side right shoes were burned down almost to where they meet the drum.

Lucky to get home. I have TPMS and heat sensors and nothing was out of line.


I find it peculiar that the destruction or failures were diagonal from each other.

I hope to get an explanation on how the electronic ABS works from both GD and Curt.

Thank you. Did they think the ABS could be linked to the brake malfunction? If not, do they have an explanation of what they think happened? Does it look like the brakes stayed on until they destroyed the equipment. TIA.

[CharlieP]

No idea yet...literally just found out. I will post here with updates as I get them. I will say this the Dealership, GD and Curt jumped right in on this one.

[huntindog]

Disc brakes and ABS go together like peanut butter and jelly.
Drum brakes and ABS are more like water and oil.

[Hoopy Frood]

I've yet to see an explanation of how ABS will work well with trailer drum brakes. Just can't see it.

[huntr70]

This is a new rig with only about 500 miles on it before this trip. I have a 2022 GMC 3500 dual wheels pulling/stopping it. The "catastrophic failure" was described by GD and Curt. The front Drivers side was a total mess. Drum destroyed, break shoes gone along with all of the parts and what was left was grinding against the drum. Passenger side rear same thing but not as bad. So both of those breaks were not working at all. Passenger front left and driver side right shoes were burned down almost to where they meet the drum.

Lucky to get home. I have TPMS and heat sensors and nothing was out of line.


I find it peculiar that the destruction or failures were diagonal from each other.

I hope to get an explanation on how the electronic ABS works from both GD and Curt.

I'm going to assume that the breakaway cable wasn't pulled out at some point?

With the new anti-lock system, you may not have immediately noticed it with a dually pulling it.

[coltss]

So we have a similar problem with our brake system also. The way I found out was on my dash a signal came up that trailer brake disconnected from vehicle which would come on and off intermittenly. I checked everything that i could while on the road with no luck. Found an RV repair shop who found the problem that i had a wire shorting out behind the hub and thats when he noticed that my brakes were shot, metal on metal on one wheel, about 25 percent left on the opposite wheel. I have approximately 4000 miles on this RV. This is a 2022 GD Solitude 2930 RL. I dont know much about brake systems but I am told these are Curt drums with toner ring, backing plates with wheel speed sensors, self adjusting brakes. I have contacted GD and have not heard anything as of yet, however I did contact the dealership and they said the brakes are only warrantied for 1 year and I am 2 months over that. Needless to say very disappointed with this system, this is our 5th RV and never had a brake isssue like this. I hope GD steps up and takes care of this issue.

[Steven@147]

The wires for the brake magnets inside the drum can come loose and short against the brake assembly whether it has ABS or not. This can happen anytime, in 2 months or 2 years of ownership, with in 100 or 10000 miles. There is just a little clip that holds the magnet wires back out of the way of the actuator assembly. Some owners have had this problem. Since its inside the brake drum you can't see it and yes you can end up with a RV Brakes Disconnected message on your tow vehicle screen when the wires short out. Thing is you have to remove the brake drum to check it out and fix the problem. It could be on any one of the wheels.

The self adjusting brake assembly works ok to keep the brake shoes properly adjusted (after initial correct adjustment) through the use of the star wheel adjuster. But that is separate from the actual braking action.

The braking action is electro/mechanical assemblies. Normally with how the electric brakes work the magnets are just a hunk of metal but when energized with electrical power, they turn into powerful magnets. The magnets are attached to the end of an actuator arm. When the magnets are energized they clamp to the inside face of the drum and drag on the drum. With the rotation of the wheel drum, the actuator arm moves and engages the brake shoes by spreading the shoes wider and they drag against the outside edges of the brake drum.

Now if everything works ok, when you take your foot off the brake pedal, the magnets are deenergized, unclamp from the inside face of the brake drum, and the actuator arm releases the braking action through the use of return springs pulling the brake shoes back together.
The assembly actuator arm inside the drum can mechanically stick or jam, and the return springs don't or can't pull the brake shoes back together and off the outside edges of the drum. Since the brake shoes are so very close to the drum under normal operation anyway it doesn't take much to stick the actuator with the brakes shoes engaged. Now your brakes for that tire / drum are locked on and will grind away until nothing is left.

Why the actuator arm might stick or jam with the brake on is usually because of a cheap or poorly assembled brake assembly, return springs not installed correctly or broken, or brake dust galling up the actuator arm (which should be lubricated) on the pivot pin so that it doesn't move freely. Free unobstructed movement of the brake magnet actuator arm should always be checked when inspecting the brake assembly and is crucial to the proper operation of the brake assembly.

With ABS drum brakes now offered on most of the new RVs the drums themselves are different and have a reluctor / toner ring. You can not or should not ever replace an ABS drum with a non-ABS drum. The brake assembly is also different in that it has a reluctor toner ring sensor and should not be replaced with a non sensor assembly.
Theory of operation - With these ABS drum brakes, each ABS toner ring sensor, on each wheel of the RV, sends a pulse back to an ABS controller. This ABS controller determines how much electrical current is applied to each wheel brake magnet to keep all wheels of the RV turning at the same rotation speed.

Side note - The only difference between the RV electro/mechanical drum brakes and hydraulically actuated drum brakes that have been around for generations is the use of a hydraulic cylinder that spreads the brake shoes apart and replaces the magnet and actuator arm. And so there are no brake magnet wires inside the brake drum on hydraulically actuated brake assemblies.

Accordingly - any of the drum brake wires whether they are along the RV frame or inside the axles tubes, or the magnet wires inside the drum, can short out and cause a brake disconnected message. As we recently had this problem. Our drum brake wires were frayed and shorting out inside the axle tubes.

No TPMS tire pressure monitoring system sensor is going to catch a stuck brake unless the brake drum gets so hot it heats up the wheel rim which in turn heats up the air inside the tire. Not likely.

This also has obsoletely nothing to do with disc brakes. Totally different systems.

[coltss]

The wires for the brake magnets inside the drum can come loose and short against the brake assembly whether it has ABS or not. This can happen anytime, in 2 months or 2 years of ownership, with in 100 or 10000 miles. There is just a little clip that holds the magnet wires back out of the way of the actuator assembly. Some owners have had this problem. Since its inside the brake drum you can't see it and yes you can end up with a RV Brakes Disconnected message on your tow vehicle screen when the wires short out. Thing is you have to remove the brake drum to check it out and fix the problem. It could be on any one of the wheels.

The self adjusting brake assembly works ok to keep the brake shoes properly adjusted (after initial correct adjustment) through the use of the star wheel adjuster. But that is separate from the actual braking action.

The braking action is electro/mechanical assemblies. Normally with how the electric brakes work the magnets are just a hunk of metal but when energized with electrical power, they turn into powerful magnets. The magnets are attached to the end of an actuator arm. When the magnets are energized they clamp to the inside face of the drum and drag on the drum. With the rotation of the wheel drum, the actuator arm moves and engages the brake shoes by spreading the shoes wider and they drag against the outside edges of the brake drum.

Now if everything works ok, when you take your foot off the brake pedal, the magnets are deenergized, unclamp from the inside face of the brake drum, and the actuator arm releases the braking action through the use of return springs pulling the brake shoes back together.
The assembly actuator arm inside the drum can mechanically stick or jam, and the return springs don't or can't pull the brake shoes back together and off the outside edges of the drum. Since the brake shoes are so very close to the drum under normal operation anyway it doesn't take much to stick the actuator with the brakes shoes engaged. Now your brakes for that tire / drum are locked on and will grind away until nothing is left.

Why the actuator arm might stick or jam with the brake on is usually because of a cheap or poorly assembled brake assembly, return springs not installed correctly or broken, or brake dust galling up the actuator arm (which should be lubricated) on the pivot pin so that it doesn't move freely. Free unobstructed movement of the brake magnet actuator arm should always be checked when inspecting the brake assembly and is crucial to the proper operation of the brake assembly.

With ABS drum brakes now offered on most of the new RVs the drums themselves are different and have a reluctor / toner ring. You can not or should not ever replace an ABS drum with a non-ABS drum. The brake assembly is also different in that it has a reluctor toner ring sensor and should not be replaced with a non sensor assembly.
Theory of operation - With these ABS drum brakes, each ABS toner ring sensor, on each wheel of the RV, sends a pulse back to an ABS controller. This ABS controller determines how much electrical current is applied to each wheel brake magnet to keep all wheels of the RV turning at the same rotation speed.

Side note - The only difference between the RV electro/mechanical drum brakes and hydraulically actuated drum brakes that have been around for generations is the use of a hydraulic cylinder that spreads the brake shoes apart and replaces the magnet and actuator arm. And so there are no brake magnet wires inside the brake drum on hydraulically actuated brake assemblies.

Accordingly - any of the drum brake wires whether they are along the RV frame or inside the axles tubes, or the magnet wires inside the drum, can short out and cause a brake disconnected message. As we recently had this problem. Our drum brake wires were frayed and shorting out inside the axle tubes.

No TPMS tire pressure monitoring system sensor is going to catch a stuck brake unless the brake drum gets so hot it heats up the wheel rim which in turn heats up the air inside the tire. Not likely.

This also has obsoletely nothing to do with disc brakes. Totally different systems.

Steven@147 Thanks for info, much appreciated