Investigations
PARKING BRAKE FAILURE
NHTSA Preliminary Evaluation PE03057 - closed, opened 2003-12-08.
NHTSA investigation PE03057 is a Preliminary Evaluation opened on 2003-12-08 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2004-04-09 - NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
A Preliminary Evaluation like PE03057 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.
Investigators summarized the matter as follows: "ODI OPENED PE03-057 TO ASSESS PARKING BRAKE INEFFECTIVENESS IN THE SUBJECT VEHICLES. THESE VEHICLES ARE EQUIPPED WITH FOUR WHEEL DISC BRAKES THAT INCORPORATE A SINGLE-SHOE DRUM-IN-HAT PARKING BRAKE INDEPENDENT OF THE SER..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time.
Investigation Summary
ODI OPENED PE03-057 TO ASSESS PARKING BRAKE INEFFECTIVENESS IN THE SUBJECT VEHICLES. THESE VEHICLES ARE EQUIPPED WITH FOUR WHEEL DISC BRAKES THAT INCORPORATE A SINGLE-SHOE DRUM-IN-HAT PARKING BRAKE INDEPENDENT OF THE SERVICE BRAKES. COMPLAINT AND WARRANTY DATA INDICATE THAT THE PARKING BRAKE LININGS TEND TO WEAR OUT EARLY IN THE LIFE OF THE VEHICLE (AT AN AVERAGE OF 24 MONTHS IN SERVICE), REDUCING THE PARKING BRAKE SYSTEM'S TORQUE BELOW THAT NEEDED TO IMMOBILIZE THE VEHICLE. GM HAS ATTRIBUTED THIS ACCELERATED WEAR TO FOREIGN MATERIAL INTRUSION AND A FAILURE OF THE BRAKE SHOE TO PROPERLY SELF-CENTER WITHIN ITS BRAKE DRUM. EFFECTIVE WITH THE START OF MY 2003 PRODUCTION, A NEWER REDUCED FORCE HOLD-DOWN CLIP WAS INTRODUCED TO FACILITATE BRAKE SHOE DISENGAGEMENT FROM THE DRUM SURFACE. THIS PART IS ALSO AVAILABLE AT THE SERVICE LEVEL FOR THE MY 1999-2002 VEHICLES. GM HAS INDICATED THAT THE PAKING BRAKE IS INTENDED TO OPERATE IN CONJUNCTION WITH THE TRANSMISSION TO IMMOBILZE PARKED VEHICLES, AND THAT IN MANY CASES, ACCELERATED PARKING BRAKE LINING WEAR IS CAUSED BY ROUGH USE, VEHICLE MODIFICATIONS, AND DRIVING WITH THE PARKING ENGAGED. ODI HAS UPGRADED THE PRELIMINARY EVALUATION TO AN ENGINEERING ANALYSIS TO GATHER FURTHER INFORMATION CONCERNING PARKING BRAKE USAGE FACTORS AND THE CIRCUMSTANCES SURROUNDING THE SEVENTEEN REPORTED VEHICLE CRASHES.
About This Investigation Type
A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. about how PlainCars sources NHTSA data.
Read our methodology - how this data is sourced, computed, and verified.