Chevrolet Silverado / GMC Sierra. Service manual — part 836

Fig. 4: Identifying Flusher Tank & Components
Courtesy of GENERAL MOTORS CORP.

IMPORTANT:

Do not substitute with solutions that contain alcohol or
glycol. Use of solutions that contain alcohol or glycol
may damage the J 35944-A , oil cooler components or
transmission components.

The J 35944-22 flushing fluid is environmentally safe, yet
powerful enough to cut through transmission fluid to
dislodge any contaminants from the cooler. The safety
precautions on the label regarding potential skin and eye
irritations associated with prolonged exposure, are
typical precautions that apply to many similar cleaning
solutions. It should be noted that according to GM, use
of other non-approved fluids for cooler flushing can have

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

2. Remove the fill cap (9) on the J 35944-A and fill the flusher tank (4) with 0.6 L (20-21 oz)

of J 35944-22 flushing solution using the measuring cup (6). Do not overfill.

3. Install the fill cap (9) on the J 35944-A and pressurize the flusher tank (4) to 550-700 kPa

(80-100 psi), using the shop air supply at the tank air valve (9).

Fig. 5: Flushing Transmission Oil Cooler Using J 35944
Courtesy of GENERAL MOTORS CORP.

4. Connect the J-44835-1 adapters to the transmission oil cooler lines.

an adverse reaction to the seals inside the transmission.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

5. Connect the J 35944-A discharge hose (5) to the oil cooler return pipe, top connector.

6. Clip the discharge hose (5) onto the oil drain container.

7. Attach the J 35944-A to the undercarriage of the vehicle with the hook provided and

connect the flushing system feed supply hose (3) from the J 35944-A to the oil cooler feed
pipe, bottom connector.

8. With the water supply valve (1) on the J 35944-A in the OFF position, connect the water

supply hose from the J 35944-A to the water supply at the faucet.

9. Turn ON the water supply at the faucet.

INITIAL FLUSH

1. Turn the J 35944-A water supply valve (1) to the ON position and allow water to flow

through the oil cooler and pipes for 10 seconds in order to remove any remaining
transmission fluid. 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.

2. Turn the J 35944-A water supply valve (1) to the OFF position and clip the discharge hose

(5) onto a suitable container, preferably with a lid, to avoid splashback.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Fig. 6: Turning J 35944-A Water Supply Valve To On Position
Courtesy of GENERAL MOTORS CORP.

3. Turn the J 35944-A water supply valve (1) to the ON position and depress the trigger (8) to

mix cooler flushing solution into the water flow. Use the clip provided on the handle to hold
the trigger (8) down. The discharge will foam vigorously when the solution is introduced
into the water stream.

IMPORTANT: Flushing for approximately 2 minutes in each cooler line

direction will result in a total of about 31-38 L (8-10 gallons)
of waste fluid. This mixture of water and flushing fluid is to

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado