Ford Ecosport: Transfer Case - 6-Speed Automatic Transmission – 6F35 / Diagnosis and Testing - Transfer Case

Principles of Operation

The AWD system may be referred to as a 4WD system in other service information and owner literature or messages located on the message center.

The transfer case or power transfer unit is a gearbox that is attached to the transmission. The RH intermediate shaft passes through the transfer case unit and engages the differential side gear as in normal FWD applications. The transfer case unit directs power to the rear driveshaft through a helical gear spline coupled to the transmission differential case, hypoid/helical ring gear assembly and pinion set. The transfer case unit is sealed from the transmission and has its own oil sump.

Serviceable components of the transfer case unit are limited to the transfer case rear seal and flange, transfer case input shaft seal (LH), transfer case input shaft seal (RH), transfer case housing O-ring seal. The internal components are not serviced. If any of the geared components, bearings, case cover or internal shafts are worn or damaged, a new transfer case unit must be installed.

Heat Protection transfer case Unit

During off-road operation or heavy trailer towing the AWD system may implement a heat protection mode to protect the transfer case from damage. The AWD system will reduce commanded torque to half as the temperature approaches its limit. Once the temperature limit is reached, then 2WD only is commanded.

For concerns with the AWD system or Automatic torque coupling (ATC),
REFER to: Four-Wheel Drive Systems (308-07A Four-Wheel Drive Systems, Diagnosis and Testing).

Inspection and Verification

1. Verify the customer concern.
   

1. Visually inspect for obvious signs of mechanical damage.
   

  Visual Inspection Chart

1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step
   

1. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.
   

Symptom Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).

In most circumstances the PCM sets a DTC to help guide with diagnostics. Refer to the DTC Chart before using the Symptom Chart. The condition column lists the vehicle condition. The Possible Sources column lists a detailed vehicle condition. The Action column lists the action to be performed to determine the cause of the condition. Each action lists the components that can cause the system and the individual components in that system. The components are listed in order of disassembly. Use the list of components and the required action to focus on disassembly inspections for the root cause of the concern.

Inspection of the seal's mating journal should be performed every time a seal is replaced. The mating part/journal should be replaced if it has any of the following conditions: Radial wear groove that is felt by running a finger nail across where the seal lip runs. Scratches, pitting, galling, nicks or other shaft damage under or near where the seal lip runs. Discoloration or coked oil on the shaft where the seal lip runs. Shaft corrosion under or near where the seal lip runs. Sharp edges or burrs on the shaft lead in chamfer. NEVER use emery cloth on journal finishes, replace the part.