Inspection and Verification
- Verify the customer concern.
- 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
- If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the cause is not visually evident, verify the symptom and GO to «Symptom Chart - Power Transfer Unit (PTU)»(ref-494586-S12395096052012081400000) .
Symptom Chart
| Condition | Possible Sources | Action |
|---|---|---|
| The Power Transfer Unit (PTU) makes noise | Tire inflation pressure Tire and wheel size Fluid level Internal components | MAKE SURE all tires and wheels are the same size and brand and the inflation pressures are correct. FILL with the correct type and amount of lubricant. REFER to POWER TRANSFER UNIT (PTU) DRAINING AND FILLING . OPERATE 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 AUTOMATIC TRANSAXLE/TRANSMISSION - 6F35 or AUTOMATIC TRANSMISSION - 6F50/6F55 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 vent | PTU over filled | REFER to ANALYSIS OF LEAKAGE . |
| Leaking automatic transmission fluid | PTU intermediate shaft seal PTU compression seal | REFER to ANALYSIS OF LEAKAGE . |
| Leaking gear lubricant from the seals | The PTU vent is plugged (located on top of the PTU) Damaged seals | INSTALL a new PTU. REFER to POWER TRANSFER UNIT (PTU) . REFER to ANALYSIS OF LEAKAGE . |
| Vehicle has no or inadequate torque at rear wheels | Rear axle PTU mechanical failure | REFER to REAR DRIVE AXLE/DIFFERENTIAL . REFER to POWER TRANSFER UNIT (PTU) . |
| Vehicle binds in a turn or resists turning/ pulsates or shudders in a straight line | Wheels/tires Brake system Wheel bearings Halfshafts Wheel speed sensor(s) ABS module | REFER to WHEELS AND TIRES . REFER to BRAKE SYSTEM - GENERAL INFORMATION . REFER to SUSPENSION SYSTEM - GENERAL INFORMATION . REFER to DRIVELINE SYSTEM - GENERAL INFORMATION . REFER to ANTI-LOCK BRAKE SYSTEM (ABS) AND STABILITY CONTROL . REFER to ANTI-LOCK BRAKE SYSTEM (ABS) AND STABILITY CONTROL . |
SYMPTOM CHART - POWER TRANSFER UNIT (PTU)