D150 1/2 Ton Pickup 2WD V6-239 3.9L VIN X FI (1988)
Fan Clutch: Testing and Inspection
Fan Looseness
Lateral movement can be observed at the fan blade tip under various temperature conditions because of the type bearing used. This movement should not
exceed 1/4 inch (6.5 mm) as measured at the fan tip. If this lateral movement does not exceed specifications, there is no cause for replacement.