GMC Yukon XL backup noise issue due to malfunctioning brakes on GMC Yukon XL

Some GMC Yukon XL owners report experiencing a squeaking noise specifically when backing up, which may not be related to malfunctioning brakes. These owners have noted that the noise could be attributed to issues with the U-joint, particularly the back U-joint or the rear-end. Additionally, some have reported loud whaling noises, which GM has acknowledged may stem from the material used in the brake pads. Furthermore, a clunk noise in the vehicle is sometimes caused by fuel movement in the tank when it is not completely full, which is considered an operating characteristic and may not require repairs. Therefore, while brake issues could be a factor, it is important for owners to consider U-joint problems, brake pad material, and fuel tank movement as potential sources of the noise.