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Transfer Case - Power Transfer Unit (Ptu): Diagnosis Mercury Sable V

Transfer Case ~106 words

Inspection and Verification

  1. Verify the customer concern.
  2. Inspect for obvious signs of mechanical damage. VISUAL INSPECTION CHART Mechanical Power Transfer Unit (PTU) Halfshafts and CV joints Driveshaft and U-joints Wheel/tire size and brand Matching tire size and brand Tire pressure
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. If the cause is not visually evident, verify the symptom and Go to «Symptom Chart - Power Transfer Unit (PTU)»(ref-293504-S38051804142008080700000) .

Symptom Chart - Power Transfer Unit (PTU)

ConditionPossible SourcesAction
The Power Transfer Unit (PTU) makes noiseTire inflation pressure Tire and wheel sizeMAKE SURE all tires and wheels are the same size and brand and the inflation pressures are correct.
Fluid levelFILL with the correct type and amount of lubricant. REFER to Power Transfer Unit (PTU) Draining and Filling .
Internal componentsOPERATE the vehicle in all gears. If there is noise in the transaxle in NEUTRAL, or in some gears and not in others, REMOVE and REPAIR the transaxle. Refer to the appropriate Automatic Transmission article for the procedure. If there is noise in all gears, INSTALL a new PTU. REFER to Power Transfer Unit (PTU) .
Leaking fluid from the PTU ventPTU over filledREFER to Analysis of Leakage .
Leaking automatic transmission fluidPTU intermediate shaft seal PTU compression sealREFER to Analysis of Leakage .
Leaking gear lubricant from the sealsThe PTU vent is plugged (located on top of the PTU)INSTALL a new PTU. REFER to Power Transfer Unit (PTU) .
Damaged sealsREFER to Analysis of Leakage .
Vehicle has no or inadequate torque at rear wheelsRear axleREFER to REAR DRIVE AXLE/DIFFERENTIAL article.
PTU mechanical failureREFER to Power Transfer Unit (PTU) .
Vehicle binds in a turn or resists turning/pulsates or shudders in a straight lineWheels/tiresREFER to WHEELS AND TIRES article.
Brake systemREFER to BRAKE SYSTEM - GENERAL INFORMATION article.
Wheel bearingsREFER to SUSPENSION SYSTEM - GENERAL INFORMATION article.
HalfshaftsREFER to DRIVELINE SYSTEM - GENERAL INFORMATION article.
Wheel speed sensor(s)REFER to VEHICLE DYNAMIC SYSTEMS article.
ABS moduleREFER to VEHICLE DYNAMIC SYSTEMS article.

Symptom Chart - Power Transfer Unit (PTU)