Mazda CX-9 Investigations (2008)

2 ODI actions on file.

• PEPE15022RECALLOpened 6/9/2015
  Lower ball joint separation
  SUSPENSION:FRONT:CONTROL ARM:LOWER BALL JOINT

  In an July 7,2015 letter to NHTSA, Mazda identified a safety defect that could result in lower ball joint separation in approximately 193,484 model year (MY) 2007 through 2014 Mazda CX-9 vehicles (NHTSA Recall No. 15V-451,Mazda 8515G).Mazda indicated that damage to the ball joint boot may allow water to enter the front suspension ball joint fitting during use which may result in premature ball joint wear and a progressively looser joint.In January 2014, Mazda implemented redesigned lower control arms in production vehicles to improve the durability of the lower ball joints.The redesign involved changing the shape of the top surface of the ball joint boot cover and adding a suspension plate to the undersurface of the knuckle.Mazda's recall will replace the defect lower control arms with the redesigned parts.ODI's analysis of information collected during PE15-022 identified a total of 62 ball joint separation incidents, including 34 identified in ODI complaints and 31 identified in Mazda complaints and field reports (3 of the Mazda records involve vehicles/incidents that were also reported to ODI).When Mazda's design change was implemented, most of the field experience related to lower ball joints involved complaints of noise and premature wear-out.Only 1 of the ODI and 6 of the additional Mazda separation complaints identified in ODI's analysis were reported prior to January 2014.Significant increases in the number and trend in separation complaints were observed in 2015, when 30 of the ODI complaints and 16 of the additional Mazda complaints were reported.The report trend appears to be accelerating, with 29 of the reports received after ODI opened PE15-022 on June 9, 2015.There has been one crash reported to ODI related to the alleged defect (VOQ 10746510). This investigation is closed based on Mazda's recall.The 34 VOQs associated with this investigation are: 10747358, 10746510, 10744897, 10743509, 10736229, 10735938, 10734763, 10734302, 10734290, 10733813, 10732578, 10732217, 10732154, 10731850, 10730736, 10730280, 10730143, 10730114, 10726622, 10726480 10726448, 10726168, 10725839, 10725567, 10725488, 10725427, 10725390, 10717510, 10714469, 10695142, 10668978, 10648429, 10640541, 10546535

• PEPE11026CLOSEDOpened 8/9/2011
  Brake master cylinder leak
  SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:MASTER CYLINDER

  The Office of Defects Investigation (ODI) opened PE11-026 to investigate possible brake performance loss due to brake fluid leaking from the master cylinder into the brake booster in model year (MY) 2008 Mazda CX-9 vehicles.In response to ODI's information request letter, Mazda identified a problem with the manufacturing process for the master cylinder primary plunger that could result in inappropriate surface finish.ODI's analysis of complaints and field reports determined that the problem was isolated to several months late in the production of the MY 2008 CX-9 vehicles.Mazda indicated that changes to the plunger machining and inspection processes were incorporated late in MY 2008 vehicle production (June 25, 2008).There are no confirmed failures related to the condition in subsequent production.The subject master cylinder was used by Mazda in MY 2007 through MY 2011 CX-9 vehicles (approximately 132,000 vehicles) with no other significant problems related to master cylinder leakage.ODI's analysis identified a total of 248 complaints and field reports potentially related to the subject condition in MY 2008 CX-9 vehicles.The majority of the records reported that brake malfunction indicator lamp (MIL) illumination was the only symptom of a problem, with only 4% (9 reports) alleging any symptoms related to brake pedal feel or effectiveness.ODI identified no crash claims related to the alleged defect.In addition, analysis of this data showed a declining trend with 90 percent of the incidents reported before January 2011.Based on the extremely slow leak rate associated with the alleged defect, the declining failure trend and the low probability that the condition would affect brake performance, this investigation is closed.The ODI reports cited above can be viewed at www-odi.nhtsa.dot.gov/owners/SearchNHTSAID under the following identification numbers (ODI Nos.): 10442322, 10419837, 10449109