PE87037 · PE
STEERING Investigation
SUMMARY OF INFORMATION FROM MANUFACTURER:BOTH CHRYSLER AND MITSUBISHIINDEPENDENTLY CONCLUDED THAT THE FAILURES WERE DUE TO SEVERE IMPACT LOADINGTRANSMITTED TO THE SHAFT BY THE STEERING LINKAGE SYSTEM -- IN OTHER WORDSSHAFT FAILURE IS THE RESULT, NOT THE CAUSE, OF THE ALLEGED COLLISIONCIRCUMSTANCES.MITSUBISHI DID STRENGTHEN THE SHAFT DURING THE 1984 MODELYEAR BY INCREASING THE SPLINE AND BEARING JOURNAL DIAMETERS.ANALYSIS:FAILING COMPONENT IS THE STEERING BOX CROSS SHAFT (OUTPUT SHAFT)WHICH BREAKS BETWEEN THE BOTTOM BEARING IN THE STEERING BOX AND THE PITMANARM.KNOWN FAILURES INVOLVE 4 WHEEL DRIVE UNITS EQUIPPED WITH POWERSTEERING.CROSS SHAFT AND PITMAN ARM SALES ARE CONSIDERABLY HIGHER ON 4WHEEL DRIVE UNITS THAN 2 WHEEL DRIVE UNITS.CHRYSLER REPORTS THE CROSSSHAFT DIAMETER WAS INCREASED IN APRIL, 1984, FOR INCREASED SHAFT STRENGTHTO IMPROVE ITS CAPABILITY TO WITHSTAND SEVERE IMPACT LOADS.PROPOSED ACTION:UPGRADE THIS PE TO AN EA.CONTACT MITSUBISHI FORINFORMATION ON COMPARABLE VEHICLES.===