Preliminary Inspection

Preliminary Inspection
These items must be checked prior to beginning the diagnostic procedures:

Know and Understand the Concern
In order to correctly diagnose a concern, first understand the customer concern or condition. Customer contact may be required in order to begin to verify the concern. Understand the conditions, including when the concern occurs. For example:
^ Hot or cold vehicle temperature
^ Hot or cold ambient temperature
^ Vehicle driving conditions
^ Vehicle loaded/unloaded

After understanding when and how the concern occurs, proceed to Verification of Condition.

Verification of Condition
This provides information that must be used in both determining the actual cause of customer concerns and carrying out the appropriate procedures.

These procedures must be used when verifying customer concerns for the transmission.

Determine Customer Concern

NOTE: Some transmission conditions can cause engine concerns. An electronic pressure control short circuit can cause engine misfiring. The torque converter clutch not disengaging will stall the engine.

Determine customer concerns relative to vehicle use and dependent driving conditions, paying attention to these items:
^ Hot or cold vehicle operating temperature
^ Hot or cold ambient temperature
^ Type of terrain
^ Vehicle loaded/unloaded
^ City/highway driving
^ Upshifting
^ Downshifting
^ Coasting
^ Engagement
^ Noise/vibration - check for dependencies, either rpm dependent, vehicle speed dependent, shift dependent, gear dependent, range dependent or temperature dependent.

Check Fluid Level and Condition

Fluid Level Check

CAUTION: The vehicle should not be driven if the fluid level is low as internal failure could result.

CAUTION: The fluid fill plug is located near the exhaust system. The exhaust will be extremely hot during this procedure.

NOTE: If the vehicle has been operated for an extended period at high highway speeds, in city traffic, during hot weather or while pulling a trailer, the fluid must cool down to obtain an accurate reading.

NOTE: If the transmission starts to slip, shifts slowly or shows signs of fluid leaking, the fluid level should be checked.

This transmission is equipped with an internal thermal bypass located in the case. This internal thermal bypass valve will shut off fluid flowing to the fluid cooler if the fluid temperature falls below normal operating temperature.





High Fluid Level

CAUTION: A fluid level that is too high can cause the fluid to become aerated due to the churning action of the rotating internal parts. This will cause erratic control pressure, foaming, loss of fluid from the vent tube and possible transmission failure.

If an overfill reading is indicated, remove any excessive fluid.

Low Fluid Level
A low fluid level can result in poor transmission engagement, slipping or failure. This may also indicate a leak in one of the transmission seals or gaskets.

Adding Fluid

CAUTION: The use of any other type of transmission fluid than specified can result in transmission failure.

CAUTION: The fluid fill plug is located near the exhaust system. The exhaust will be extremely hot during this procedure.

CAUTION: The vehicle should not be driven if the fluid level is low as internal failure could result.

NOTE: If the vehicle has been operated for an extended period at high highway speeds, in city traffic, during hot weather or while pulling a trailer, the fluid must cool down to obtain an accurate reading.

Add fluid using the refill procedure.

Fluid Condition Check
1. Check the fluid level.
2. Remove the fluid fill plug and fluid level indicator and allow the fluid to drip onto a facial tissue and examine the stain.
3. Observe the color and the odor. The color under normal circumstances should be dark reddish, not black or have a burnt odor.
4. If evidence of solid material is found, the transmission fluid pan should be removed for further inspection.
5. If the stain is a foamy pink color, this may indicate coolant in the transmission. The engine cooling system should also be inspected at this time.
6. If fluid contamination or transmission failure is confirmed by the sediment in the bottom of the fluid pan, the transmission must be disassembled and completely cleaned. This includes the torque converter and fluid cooler tubes. A new oil-to-air (OTA) cooler must be installed.