Chevrolet Silverado / GMC Sierra. Manual - part 743
Time allowance for performing the cooler flow checking and flushing procedure has been
included in the appropriate labor time guide operations since the 1987 model year. The service
procedure steps for oil cooler flushing and flow testing are as follows:
COOLER FLOW CHECK AND FLUSHING STEPS
1. Machine Set-up
2. Determine Minimum Flow Rate
3. Back Flush
4. Forward Flush
5. Flow Test
6. Code Recording Procedure
7. Clean-up
Tools Required
J 45096 Transmission Oil Cooling System Flush and Flow Test Tool
J 45096-30 Transmission Cooler Flush Adapter. See Special Tools.
Shop air supply with water/oil filters, regulator and pressure gage - minimum 90 psi
Eye protection
Rubber gloves
MACHINE SET-UP
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,
Sierra & Silverado
Fig. 9: View Of Main Power Switch & Main Function Switch
Courtesy of GENERAL MOTORS CORP.
1. Verify that the main power switch (1) is in the OFF position.
2. Place the main function switch (2) in the IDLE position.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,
Sierra & Silverado
Fig. 10: Connecting To 12V DC Power Source
Courtesy of GENERAL MOTORS CORP.
3. Connect J 45096 to the vehicle 12V DC power source by connecting the red battery clip to
the positive, +, battery post on the vehicle and connect the negative lead to a known good
chassis ground.
4. Turn the main power switch to the ON position.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,
Sierra & Silverado
Fig. 11: Filling Supply Tank With Transmission Fluid
Courtesy of GENERAL MOTORS CORP.
NOTE:
Do not overfill the supply vessel. Damage to the unit may
result. To verify the fluid level, view the LCD screen display
while filling the unit, to ensure the fluid level does not exceed
30 L (32 qt).
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,
Sierra & Silverado