Hummer H3. Manual — part 732

See Special Tools. If water does not flow through the oil cooler and pipes, the cause of the
blockage must be diagnosed and the plugged component must be repaired or replaced.
Continue with the cooler flushing and flow check procedure once the blockage is corrected.

6. Turn the J 35944-A water supply valve (3) to the OFF position and clip the discharge hose

onto a 19 liter (5 gallon) pail with a lid, to avoid splashback. See Special Tools.

Fig. 25: Turning The J 35944-A Water Supply Valve To The ON Position
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Flushing for approximately 2 minutes in each cooler line

direction will result in a total of about 30-38 L (8-10 gallons)

2007 Hummer H3

2007 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - H3

7. Turn the J 35944-A water supply valve (3) to the ON position and depress the trigger (1) to

mix cooler flushing solution into the water flow. See Special Tools. Use the clip provided
on the handle to hold the trigger (1) down. The discharge will foam vigorously when the
solution is introduced into the water stream.

8. Flush the oil cooler and pipes with water and solution for 2 minutes. During this flush,

attach the shop air supply 825 kPa (120 psi) to the flushing system feed air valve (2) located
on the J 35944-A , for 3-5 seconds at the end of every 15-20 second interval to create a
surging action. See Special Tools.

9. Release the trigger (1) and turn the J 35944-A water supply valve (3) to the OFF position.

See Special Tools.

Forward Flush

of waste fluid. This mixture of water and flushing fluid is to
be captured in a bucket or similar container.

2007 Hummer H3

2007 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - H3

Fig. 26: Connecting J 35944 To Oil Cooler
Courtesy of GENERAL MOTORS CORP.

1. Disconnect both hoses (1 and 2) from the oil cooler pipes and connect them to the opposite

oil cooler pipe. This will allow the oil cooler and pipes to be flushed in the normal flow
direction.

2. Repeat Step 6 and 7 of the Back Flush.

2007 Hummer H3

2007 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - H3

Fig. 27: Turning The J 35944-A Water Supply Valve To The ON Position
Courtesy of GENERAL MOTORS CORP.

3. Release the trigger (1) of the J 35944-A and allow water only to rinse the oil cooler and

pipes for 1 minute. See Special Tools.

4. Turn the J 35944-A water supply valve (3) to the OFF position and turn OFF the water

supply at the faucet. See Special Tools.

5. Attach the shop air supply to the flushing system feed air valve (2) on the J 35944-A and

blow out the water from the oil cooler and pipes. See Special Tools. Continue, until no
water comes out of the discharge hose.

2007 Hummer H3

2007 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - H3