Holden studies indicate that plugged or restricted transmission oil coolers and pipes cause insufficient transmission lubrication and elevated operating temperatures which can lead to premature transmission failure. Many repeat repair cases may have been prevented by following published procedures for transmission oil cooler flushing and flow checking. This procedure includes flow checking and flushing the auxiliary transmission oil cooler, if equipped.

Only DEXRON®VI automatic transmission fluid should be used when doing a repair on a Holden transmission.

Tools Required

Reverse Flush

1. Disconnect both fluid lines at the transmission and cooler hoses / lines at the radiator cooler
2. Check the cooler hoses / lines to radiator cooler fittings sealing washers for damage, replace as required.
3. Carefully check the radiator cooler lower fitting to see if any foreign material is evident at this point. If foreign material is found, remove it with a suitable tool and/or compressed air at a reduced pressure of approximately 345 kPa (50 psi) blown in the reverse direction through the cooler.
4. Using compressed air at a reduce pressure of approximately 345 kPa (50 psi) blown in a reverse direction, clean the fluid lines, cooler hoses / lines and if required any external cooler (where fitted).

Important: Do not reconnect the fluid inlet line at the transmission end. This line needs to be left disconnected to perform the flow rate test.

5. Perform the flow rate test
6. If the flow rate is satisfactory, reconnect the fluid inlet line to the transmission

Flow Rate Test

1. Ensure the transmission fluid is at the recommended level or slightly above
2. Disconnect the fluid inlet line at the transmission
3. Place a suitable size container underneath the disconnected fluid inlet line
4. With the selector lever in the P position, start the engine and observe the fluid flow into the container after all the air bubbles have ceased and a steady flow is evident. Measure the flow rate over 20 seconds and make sure it is within the specification.

· Transmission fluid flow rate specification per 20 Seconds:

· Temperature: Ambient 0.7 Litres

· Temperature: 86° - 93° C 1.2 Litres

5. If the flow rate is less than the specification, the cause of the low flow rate must be located and rectified. Possible cause may include:

· restricted cooler within the radiator tank

· damaged or restricted external cooler, where fitted,

· kinked or damaged transmission fluid lines and/or cooler hoses / lines, or

· internal transmission fault such as a faulty pump

6. Reinstall the fluid inlet line to the transmission