On April 29, 2015, the Office of Defects Investigation (ODI) opened PE15-017 to investigate a report alleging incidents of front brake hose failure in model year (MY) 2015 Ford Explorer Police Interceptor vehicles used by the Sacramento Police Department in its pursuit driving training program (VOQ 10705832).On September 28, 2015, ODI upgraded the investigation to an Engineering Analysis (EA15-005) to assess maximum front caliper crimp temperatures under various test conditions, test hose assemblies removed from police interceptor service for any signs of thermal degradation, and further assess field data for evidence of a defect trend related to the alleged defect.The alleged defect results from exposure to extremely high heat at the caliper-side hose crimp. NHTSA?s vehicle testing suggests that the conditions necessary to produce the critical temperatures in the subject components result from drive-soak intervals that can occur during the Sacramento training program.NHTSA's testing of hose assemblies returned from police interceptor service did not identify any evidence of thermal degradation.NHTSA has not confirmed any incidents of caliper crimp failures due to overheating in vehicles not subjected to the Sacramento training course driving.The low number of hose assembly failure reports and the absence of any verified incidents of heat related front brake hose crimp failures since 2015 suggests that the Sacramento PD incidents resulted from conditions unique to the training program.A safety related defect trend has not been identified at this time and further use of Agency resources does not appear to be warranted.Accordingly, this investigation is closed.The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist.The Agency will take further action if warranted by the circumstances.For additional information, see the Closing Report in the document file for EA15-005 on www.nhtsa.gov.
