Investigations
INEFFECTIVE AIR BRAKES
NHTSA Preliminary Evaluation PE86073 - closed, opened 1986-08-13.
NHTSA investigation PE86073 is a Preliminary Evaluation opened on 1986-08-13 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 1986-10-16 - 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 PE86073 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: "SUMMARY OF INFORMATION FROM MANUFACTURER: NONE AT THIS TIME.ANALYSIS: A PNEUMATIC BALANCE TEST PERFORMED ON FOUR OF THE SUBJECT BUSESBY AFTERMARKET BRAKE SYSTEM DISTRIBUTOR INDICATED THAT DURING A 15 PSIBRAKE APPLICATION..." 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
SUMMARY OF INFORMATION FROM MANUFACTURER: NONE AT THIS TIME.ANALYSIS: A PNEUMATIC BALANCE TEST PERFORMED ON FOUR OF THE SUBJECT BUSESBY AFTERMARKET BRAKE SYSTEM DISTRIBUTOR INDICATED THAT DURING A 15 PSIBRAKE APPLICATION, THERE WOULD BE 15 PSI AT THE FRONT AXLE AND 0 PSI ATTHE REAR. ONE OF THE KEYS TO BRAKE BALANCE IS BRAKE ACTUATION AND RELEASE.THE REAR SHOULD APPLY BEFORE THE FRONT AND RELEASE SLIGHTLY AFTER. SINCEMOST BRAKING OCCURS BELOW 20 PSI, IT WOULD SEEM THAT HAVING THE SAME ORCLOSE PRESSURE IN ALL CHAMBERS IS IMPORTANT FOR PROPER BALANCE.PROPOSED ACTION: OPEN A PE. SEND AN IR.
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.