Hopefully it just a squeaky spring. Brake shoes are hygroscopic, meaning they will absorb moisture from the air and may expand slightly. If your RV has been in storage for a while, especially in a damp place, could be the shoes are making slight contact with the drum and slight movement from walking inside may cause the wheel to rock back & forth enough to squeak a little. Additionally, the drum/rotor could develop a thin film of rust while in storage which rubs off the first time you apply the brakes. Another possibility if the noise is in fact coming from the brakes is, when you had your bearings serviced did the tech remove the drums, disassemble & repack and install new seals? Some AF axles use a grease fitting that is supposed to lube the bearings by judiciously squeezing a little grease into the bearings. Too much grease will cause some to get past the seal and onto the brake drum, not a good scenario as it can cause brake lockup, sticking, noise, damaged shoes etc. Wouldn't hurt to check, the only real fix for this is to replace the affected shoes and drum. Another check you can make is to pull the breakaway plug on your trailer brakes, which will lock them up and stop the noise. Don't forget to reset the breakaway brake switch or it will drain your batteries in a hurry!
2004.5 GMC SLT CCLB, Ride Rites, Turbo brake, EFI Live
2012 Arctic Fox 29 5T 5th Airborne, B&W, Prodigy
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