Defect Investigation Detail

CLASSIC / TIFFANY / 9999

Components - Details
NHTSA Action Number: EA87014 Vehicale/Equipment Name: CLASSIC
Vehicale/Equipment Model: TIFFANY Vehicale/Equipment Year: 9999
Component Name: STEERING Manufacturer's Name: Classic Trailers, Inc.
Date Opened: Mar, 24 1987 Date Closed: May, 20 1987
Subject: STEERING CONTROL Summary: Analysis:classic tiffany vehicles are greatly modified or altered fordcougar vehicles and represent an extremely low production volume.in thearea of concern in this engineering analysis, the modification consists ofwelding a lengthened steel undercarriage to the front of the body andchassis to extend the wheelbase by 38 inches.the subject vehicles havethe steering extended by means of an intermediate shaft supported by twopillow blocks and joined to the original steering shaft by a universaljoint.classic's response to the special order disclosed that a consulting engin-eer had been engaged to analyze the steering system problems and suggestcorrections.his test report disclosed that the "cyclic steering wheeltorque variations" were "entirely due to improperly phased and supporteduniversal joint."the engineer reported that the steering effortfluctuations varied between 200% and 300%, maximum to minimum ratio withpeaks and valleys being disposed 90 degrees.he concluded that the solecause of the fluctuations was the random installation of four universaljoints compounded by support bearings installed on shafting that should nothave been restrained.he recommended the use of a flexible steering shaftinstead of the universal joints to achieve a uniform steering torquethroughout 360 degrees of rotation.his report showed that he had introduced severe, combined torsional andbending loads on the vehicle chassis and found that there was no measure-able change in the cyclic torsional effort variation.in addition to the recommended use of a flexible steering shaft, theengineer recommended the incorporation of a manifold heat shield tominimize the amount of heat radiated into the steering components.healso recommended institution of an accelerated durability test of thesystem.the engineer's finding satisfies odi's concern that torsional and bendingloads might adversely affect vehicle steering.status:this engineering analysis was closed on may 20, 1987.===