Investigations
FRONT BRK CALIPER SEIZURE
NHTSA Preliminary Evaluation PE87015 - closed, opened 1987-01-15.
NHTSA investigation PE87015 is a Preliminary Evaluation opened on 1987-01-15 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 1987-11-30 - 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 PE87015 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: "ANALYSIS: ALLEGEDLY, DURING BRAKE APPLICATION THE DISC BRAKE CALIPERSSEIZE, RESULTING IN EXCESSIVE PULL AND/OR FRONT BRAKE LOCK-UP. SOMEREPORTS CITE A COMPLETE LOSS OF VEHICLE CONTROL RESULTING IN UNFOREWARNEDAND UNAVOID..." 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
ANALYSIS: ALLEGEDLY, DURING BRAKE APPLICATION THE DISC BRAKE CALIPERSSEIZE, RESULTING IN EXCESSIVE PULL AND/OR FRONT BRAKE LOCK-UP. SOMEREPORTS CITE A COMPLETE LOSS OF VEHICLE CONTROL RESULTING IN UNFOREWARNEDAND UNAVOIDABLE TRAVEL INTO OPPOSING TRAFFIC LANES. CONSUMERS CLAIM THATSERVICE PERSONNEL HAVE CONSISTENTLY ATTRIBUTED THE PROBLEM TO THE USE OFPHENOLIC PISTONS WHICH OVERHEAT AND SEIZE IN THE CALIPER BORES.INFORMATION PROVIDED BY THE MANUFACTURER DISCLOSED THE COMPLAINT, ACCIDENT,AND INJURY STATISTICS TABULATED ABOVE. OTHER MANUFACTURER-SUPPLIED DATADISCLOSED THAT TWO DESIGN CHANGES WITH POTENTIAL RELEVANCE TO THIS MATTERWERE MADE DURING THE PRODUCTION YEARS IN QUESTION. IN OCTOBER 1981, THESPECIFICATION OF THE MAXIMUM OUTSIDE DIAMETER OF THE PISTON WAS DECREASEDBY 0.0250 MM AND THE MINIMUM INSIDE DIAMETER OF THE CALIPER PISTON BOREINCREASED BY 0.024 MM. THESE CHANGES WERE MADE TO REDUCE THE POSSIBILITYOF PREMATURE WEAR OF THE FRONT DISC BRAKE PADS. A SECOND DESIGN REVISIONWAS MADE IN SEPTEMBER 1986 TO REDUCE INADVERTENT CHIPPING OF THE CALIPERPISTONS DURING BRAKE PAD REPLACEMENT. WARRANTY CLAIM DATA WERE INCONCLUS-IVE IN IDENTIFYING A FAILURE TREND ACCOMPANIED BY RISK OF ACCIDENTS.THE HISTORY OF BRONCO BRAKE PULL/DRIFT COMPLAINTS DISCLOSED THAT FORD HADKNOWLEDGE OF THE PROBLEM. AN AUGUST 1986, FORD TRUCK INTEROFFICE LETTERDISCUSSED THE PHENOMENON AND PROVIDED SUGGESTIONS TO REMEDY THE PROBLEMIN THE FIELD. THE CONDITION WAS DEFINED AS "RECESSION STEER", MANIFEST TOTHE VEHICLE OPERATOR AS DRIFT OR PULL UPON BRAKE APPLICATION. IN FACT,THE SENSATION WAS ATTRIBUTED TO A NET STEER TO THE LEFT WHEN THE FRONTSUSPENSION MOVES REARWARD UNDER BRAKING FORCES.CONCLUSION: SEIZURE OF THE FRONT CALIPER PISTONS HAS NOT BEEN IDENTIFIEDAS THE ORIGIN OF THE ALLEGED PROBLEM. ADDITIONALLY, THE HISTORICAL DATAALLEGING LOSS OF VEHICLE CONTROL, ACCIDENTS, AND INJURIES DO NOT IDENTIFYA SAFETY-RELATED DEFECT IN EITHER THE BRAKING OR SUSPENSION SYSTEM OF THESUBJECT VEHICLES.======
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.