Defect Report

May 16, 1989

Associate Administrator for Enforcement National Highway Traffic Safety Administration 400 Seventh Street, S.W. Washington, D.C. 20590

Pursuant to Part 573 of Title 49 of the Code of Federal
Regulations - Defect and Noncompliance Reports, Ford Motor Company is submitting information concerning a safety-related recall we are initiating. Specific information is as follows:

573/5 (c) (2)

1989 Thunderbird and Cougar vehicles produced at the Lorain, Ohio assembly plant from January 10, 1989 through January 20, 1989.

573.5 (c) (3)

Approximately 10,600 units.

573.5 (c) (4)

Approximately one percent.

573.5 (c) (5)

A small number of the subject vehicles may have been produced with improperly heat treated rear susuension knuckles. Testing has determined that these knuckles could experience high mileage fatigue cracks and eventual fracture. Should a fracture occur, the rear suspension at that wheel would not remain intact and vehicle control could be adversely affected.

573.5 (c) (6)

On January 31, 1989 it was reported that some 1989 Thunderbird and Cougar rear suspension knuckles were exhibiting poor machinability during the manufacturing process. Subsequent investigation found that one lot from the casting supplier had not been properly heat treated. Knuckles produced from this lot were purged from the system; however, 133 suspect knuckles
had been installed in the subject vehicles that had been shipped from the plant. Based on vehicle durability testing conducted with knuckles from this lot, Ford engineers predict that the knuckles could experience high mileage fatigue cracks and eventually fracture. Ford is not aware of any field reports concerning this condition.

573.5 (c) (8)

Owners of record will be notified of the condition and instructed to return their vehicles for inspection of the heat treat lot code that is stamped on the rear suspension knuckles. Dealers will replace those knuckles found to have the affected lot codes.

573.5 (c) (9)

Ford plans to make a public statement concerning the subject matter of this recall. Copies of notification letters to dealer and owners from Ford Parts and Service Division will be forwarded.