6HP26 - Automatic Transaxle/Transmission
Preliminary Inspection
The following 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 complaint 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
The following information must be used in both determining the actual cause of customer concerns and carrying out the appropriate procedures.
The following 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 the following items:
^ Hot or cold vehicle operating temperature
^ Hot or cold ambient temperatures
^ 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 Transmission Fluid Level and Condition
Transmission Fluid Level Check
CAUTION: The vehicle should not be driven if the transmission fluid level is low as internal failure may result.
NOTE: The transmission fluid temperature must be between 30° C-50° C (86° F-122° F) when checking the transmission fluid level. A higher temperature will result in an underfill condition. A lower temperature will result in an overfill condition.
This vehicle is not equipped with a transmission fluid level indicator. An incorrect transmission fluid level may affect the transmission operation and can result in transmission failure.
Under normal circumstances, the transmission fluid level should not be checked during normal maintenance. If the transmission starts to slip, shifts slowly or shows signs of transmission fluid leaking, the transmission fluid level should be checked.
1. With the selector lever in PARK, the engine at idle (550-750 rpm) and foot pressed on the brake, move the selector lever through each gear and allow engagement of each gear. Place the selector lever in the PARK position.
2. With the engine idling (550-750 rpm) in PARK, position it on a hoist.
3. Remove the transmission fluid fill plug located on the side of the transmission case.
4. Partially add transmission fluid until transmission fluid starts to come out. Wait until the transmission fluid stops or just drips from the hole.
5. Install the transmission fluid fill plug.
^ Tighten to 35 Nm (26 lb-ft).
High Transmission Fluid Level
CAUTION: A transmission fluid level that is too high may cause the transmission fluid to become aerated due to the churning action of the rotating internal parts. This will cause erratic control pressure, foaming, loss of transmission fluid from the vent tube and possible transmission failure.
If an overfill reading is indicated, drain and refill the transmission.
Low Transmission Fluid Level
A low transmission 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 Transmission Fluid
CAUTION: The use of any other type of transmission fluid than specified may result in transmission failure.
If transmission fluid must be added, add transmission fluid in 0.5L (1/2 qt) increments through the transmission fluid fill plug. Do not overfill the transmission fluid. For transmission fluid type, refer to the specification chart.
Transmission Fluid Condition Check
1. Check the transmission fluid level.
2. Remove the transmission fluid fill plug and allow the transmission fluid to drip onto a facial tissue and examine the stain.
3. NOTE: The transmission fluid could be 2 different colors. The factory fill transmission fluid is clear amber. The replacement transmission fluid is red.
Observe the color and the odor. The color under normal circumstances should be dark reddish or amber, 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 transmission fluid contamination or transmission failure is confirmed by the sediment in the bottom of the transmission fluid pan, the transmission must be disassembled and completely cleaned. This includes the torque converter and transmission fluid cooler tubes. A new oil-to-air cooler must be installed.
Water in Transmission Fluid
To correctly repair an automatic transmission or transaxle that has had water or coolant introduced into the system, completely disassemble, clean and replace the following parts:
^ All internal and external seals
^ All friction material; clutches and bands
^ Torque converter
^ All parts with bonded seals
^ All solenoids
^ All transmission fluid filters
Prior to installing the transmission or transaxle, the transmission fluid cooler(s), transmission fluid cooler tubes and transmission fluid cooler hoses need to be flushed and cleaned.