There is a rumbling noise when I drive that turns into a loud roar, similar to that of an airplane lifting off, when I apply the brakes. It happens even if I am applying them gently. What could be causing this? There is no squealing noise, and it is coming from the rear of the vehicle.
Most common reason for the rumbling noise described is a brake issue. Most likely the brake pads have completely worn away and you are metal on metal. Disassembly of the brakes will be required for an accurate inspection to be performed. You will probably need to have the rear brake pads and brake rotors replaced. Would also be a good idea to have the rear brake calipers inspected for any damage.
Brake Caliper Inspection
Inspect the disc brake caliper for the following:
- Brake fluid leaks in and around boot area and inboard lining
- Ruptures, brittleness or damage to the piston dust boot
- Damaged, dry or brittle guide pin dust boots
If caliper fails inspection, disassemble and recondition caliper, replacing the seals and dust boots.