Investigation PE11008: Vehicles

Status

CLOSED

Opened

Mar 29, 2011

Closed

Jan 30, 2012

Model years

—

Subject

Caterpillar C7 Hose Leak

Component: Engine and engine cooling › Engine › Diesel

Summary

The Office of Defects Investigation (ODI) received 1 fleet complaint (involving 8 incidents on 6 vehicles) alleging that the Clean Gas Induction (CGI) coolant lines on affected vehicles had developed leaks resulting in a vehicle stall.Caterpillar conducted system testing and determined that coolant in the subject engines may become increasingly acidic over time, which may result in damage to the inner walls of the coolant hoses.In at least four (4) cases this has resulted in stranded school buses due to coolant loss.Caterpillar (CAT) submitted a recall notice on December 2, 2011.CAT's announcement of a safety recall on this matter addresses ODI's concerns.Coolant will be checked and changed more frequently to prevent in-field pH degradation and coolant hoses damaged from this issue will be replaced under warranty. The subject vehicles have been recalled, therefore this investigation is closed.The ODI report cited above can be reviewed at www-odi.nhtsa.dot.gov/owners/SearchNHTSAID under the following identification (ODI) number: 10446420

An NHTSA investigation looks into whether a safety defect exists. Opening one is not a finding. Outcomes can include a recall, closure without action, or further inquiry.