2004 Mitsubishi Montero Limited: Hydraulic Brake Booster is malfunctioning, making a ("gobble-gobble", squirrel-like chirping sound) almost every time the brake pedal is pressed. Hwy driving, without the use of brakes, the frequent "chirping" sounds still occur. Under medium to heavy braking, the vehicle shudders and shakes. This specific sound is made in all gear selections and even when the car's battery is on/engine off. Upon inspection of the hydraulic brake booster under the hood, the unit shakes when the chirp sound is made. Duration of the sound lasts around one second and it happens frequently (5-10 times per minute).

- Aliso Viejo, CA, USA

The contact owns a 2004 Mitsubishi Montero. While driving approximately 60 mph and attempting to engage the brakes, the brake pedal was hard to depress. The emergency brake had to be activated in order to stop the vehicle. Also, the contact heard an abnormal noise from the driver side of the instrument panel when the brakes were applied. The dealer stated that the hydraulic booster system needed to be replaced. The vehicle was not repaired. The manufacturer was notified and informed the contact that the vehicle was previously remedied according to NHTSA campaign number: 01V254001 (service brakes, hydraulic). The approximate failure mileage was 189,000.

- Memphis, TN, USA