Symptom Chart: PTU
WARNING: This page is about a different variant/trim than selected.
Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Service Information for information regarding Ford-specific diagnostic practices.
| Condition | Possible Sources | Actions |
|---|---|---|
| Odor from the PTU may be detected as propane or a natural gas type of odor | Overheated PTU fluid from idler bearing walk | REMOVE the PTU. REFER to Power Transfer Unit (PTU) -- 3.5L GTDI , Power Transfer Unit (PTU) -- 3.5L Ti-VCT or Power Transfer Unit (PTU) -- 3.7L Ti-VCT . DISASSEMBLE the PTU and INSPECT for damage caused by the idler shaft bearing. REFER to Power Transfer Unit (PTU) -- Overhaul . INSTALL the idler shaft bearing repair kit as necessary. REFER to Install Idler Shaft Bearing Repair Kit . |
| The PTU makes noise | Tire inflation pressure Tire and wheel size |
VERIFY all tires and wheels are the same size and brand and the inflation pressures are correct. |
| Fluid level | FILL with the correct type and amount of lubricant. Refer to Power Transfer Unit (PTU) Draining and Filling . | |
| PTU idler bearing walk | REMOVE the PTU. REFER to Power Transfer Unit (PTU) -- 3.5L GTDI , Power Transfer Unit (PTU) -- 3.5L Ti-VCT or Power Transfer Unit (PTU) -- 3.7L Ti-VCT . DISASSEMBLE the PTU and INSPECT for damage caused by the idler shaft bearing. REFER to Power Transfer Unit (PTU) -- Overhaul . INSTALL the idler shaft bearing repair kit as necessary. REFER to Install Idler Shaft Bearing Repair Kit . |
|
| Leaking fluid from the PTU vent | PTU overfilled | VERIFY fluid level. REFER to Power Transfer Unit (PTU) Draining and Filling |
| PTU overheat from idler bearing walk | REMOVE the PTU. REFER to Power Transfer Unit (PTU) -- 3.5L GTDI , Power Transfer Unit (PTU) -- 3.5L Ti-VCT or Power Transfer Unit (PTU) -- 3.7L Ti-VCT . DISASSEMBLE the PTU and INSPECT for damage caused by the idler shaft bearing. REFER to Power Transfer Unit (PTU) -- Overhaul . INSTALL the idler shaft bearing repair kit as necessary. REFER to Install Idler Shaft Bearing Repair Kit . |
|
| PTU overfilled and transmission fluid is low. | INSTALL new compression seal, intermediate shaft seal, deflector and alignment washer. REFER to Input Shaft Seal and Intermediate Shaft Seal and Deflector . DRAIN and REFILL the PTU. REFER to Power Transfer Unit (PTU) Draining and Filling . | |
| PTU vent hose is disconnected or missing | CONNECT the PTU vent hose or INSTALL a new PTU vent hose as necessary. | |
| Leaking automatic transmission fluid (Red fluid) | Damaged or worn PTU intermediate shaft seal | INSTALL a new intermediate shaft seal, deflector and alignment washer. REFER to Intermediate Shaft Seal and Deflector . |
| Damaged or worn PTU compression seal | INSTALL a new compression seal, intermediate shaft seal, deflector and alignment washer. REFER to Power Transfer Unit (PTU) -- 3.5L GTDI , Power Transfer Unit (PTU) -- 3.5L Ti-VCT Power Transfer Unit (PTU) -- 3.7L Ti-VCT , and Intermediate Shaft Seal and Deflector . | |
| Leaking gear lubricant from the seals (Brown fluid) | Damaged cover seal | INSTALL a new PTU cover seal. REFER to Cover Seal . |
| Damaged pinion seal and/or pinion flange seal mating surface | INSTALL a new pinion seal and pinion flange as needed. REFER to Output Shaft Seal . | |
| The vent on top of the PTU is plugged (vent hose equipped) | INSTALL a new PTU vent hose. | |
| The vent on top of the PTU is plugged (jiggle cap equipped) | Pressurize the PTU through the fill plug to verify. REFER to Power Transfer Unit (PTU) Draining and Filling . | |
| Vehicle has no or inadequate torque at rear wheels | Rear axle | Refer to Rear Drive Axle/Differential , Overview. |
| PTU mechanical failure | INSTALL a new PTU. REFER to Power Transfer Unit (PTU) -- 3.5L GTDI Power Transfer Unit (PTU) -- 3.5L Ti-VCT Power Transfer Unit (PTU) -- 3.7L Ti-VCT . | |
| Vehicle binds in a turn or resists turning/pulsates or shudders in a straight line | Wheels/tires | Refer to Wheels and Tires . |
| Brake system | Refer to Brake System - General Information , Symptom Chart: Brake System. | |
| Wheel bearings | Refer to Suspension System - General Information , Symptom Chart: Suspension System. | |
| Halfshafts | Refer to Driveline System - General Information , Symptom Chart: NVH. | |
| Wheel speed sensor(s) | Refer to Anti-Lock Brake System (ABS) and Stability Control , Symptom Chart: Vehicle Dynamic Systems. | |
| ABS module | Refer to Anti-Lock Brake System (ABS) and Stability Control , Symptom Chart: Vehicle Dynamic Systems. |