No Drive or No Reverse (Replace Lower Transmission Oil Cooler Hose Assm)

Some customers may comment that the transmission has no drive or no reverse. Also, visual inspection of the transmission fluid may show a burnt appearance.

This condition may be caused by a twist in the lower transmission cooler hose at the radiator end. The twist is caused by allowing the hose to rotate when tightening the fitting at the transmission. The twist causes the rubber hose portion of the line to kink and cut off fluid flow to the cooler.

Inspect the lower transmission oil cooler hose for a twist. The area of the hose most likely to twist is difficult to see because the hose is obscured by the lower radiator hose. If there is any indication of a twist, replace the lower transmission oil cooler hose assembly using the following service procedure and part number.

1. Remove the upper radiator core support brace bolts and the brace.
2. Remove the bolts attaching the left cooling fan.
3. Disconnect the electrical connector at the left cooling fan and remove the fan.
4. Remove the air intake duct.
5. Disconnect the oil cooler hose fitting from the radiator.
6. Disconnect the oil cooler hose fitting from the transmission.
7. Remove the lower transmission oil cooler hose assembly from the vehicle.
8. Install the lower transmission oil cooler hose assembly in the vehicle.
9. Connect the oil cooler hose fitting to the radiator.

Tighten
Tighten the hose fitting to 27 N·m (20 lb ft).

10. Connect the oil cooler hose fitting to the transmission.

Notice: While tightening the fitting at the transmission, be sure to hold the position of the hose. This will prevent the hose from twisting. Failing to do so may kink the hose and cut off fluid flow to the cooler and damage the transmission.

Tighten
Tighten the hose fitting to 22 N·m (16 lb ft).

11. Install the air intake duct.
12. Install the left cooling fan and connect the electrical connector.
13. Install the bolts attaching the left cooling fan.
14. Install the upper radiator core support brace and the bolts.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: