Service Update for Inventory Vehicles Only - Water in Transmission Fluid - Expires June 30, 2007

THIS SERVICE UPDATE INVOLVES VEHICLES IN DEALER INVENTORY ONLY AND WILL EXPIRE JUNE 30, 2007.

This bulletin provides a service procedure to flush and refill the transmission fluid on certain 2007 Buick Lucerne and Cadillac DTS vehicles, equipped with 4T80E (RPO MH1) transmissions. Some of the transmissions in these vehicles may have excessive water in the transmission fluid.

This service procedure should be completed on involved vehicles currently in dealership inventory as soon as possible, but no later than June 30, 2007, at which time this bulletin will expire.

A list of involved vehicles currently in dealer inventory is attached to the Administrative Message (US) or Dealer Communication (Canada) used to release this bulletin.

Important: Dealers are to confirm vehicle eligibility by using the GM Vehicle Inquiry System (GMVIS).

Parts required to complete this service update are to be obtained from General Motors Service and Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts should be ordered on a CSO = Customer Special Order.

Important: Due to the limited number of vehicles involved, dealers are encouraged not to order parts for use as shelf stock. The transmission cooler hose should only be ordered when the commercial transmission flush and refill equipment is NOT available.

Transmission Flush and Refill Procedure for Commercially Available Equipment

Important: For those dealers with commercially available transmission fluid exchange equipment, you may utilize this equipment to complete this process. The total quantity of DEXRON VI which should be exchanged is 32 quarts (8 gallons) (30 litres). Refer to the manufacturer instructions for proper connection of the transmission fluid exchange equipment and adhere to manufacturer cautions to prevent incorrect connection and transmission damage.

1. Flush and refill the transmission using your commercially available equipment with Dexron VI automatic transmission fluid.
2. To ensure proper transmission fluid level after refill:

•	Remove the fluid level indicator.

•	Add fluid to the level at which it just registers on the indicator.

•	Re-install the fluid level indicator.

•	Start the engine and operate the vehicle for 15 minutes or until the transmission fluid reaches an operating temperature of 82-93°C (180-200°F).

•	Park the vehicle on a level surface.

•	With your foot on the brake pedal, move the shifter lever through each gear range, pausing for about 3 seconds in each range. Then, position the shift lever in PARK (P).

•	Apply the parking brake and let the engine idle for 3 minutes.

•	Remove the transmission fluid level indicator, wipe the indicator clean, and reinsert the indicator. Give the indicator a full twist to close.

•	Wait 3 seconds and remove the indicator.

•	Read both sides of the indicator. The fluid must be within the hot cross-hatched area using the lowest level reading.

Optional Transmission Flush and Refill Procedure

Important: Dealers who do not have transmission fluid exchange equipment can utilize the following procedure to flush the transmission fluid. An additional transmission cooler hose (Part number 25769586) must be obtained in order to perform the following procedure. These hoses are currently in short supply. Only one per dealer is recommended as the hose will service multiple vehicles.

1. Raise and support the vehicle.
2. Place a drain pan under the transmission bottom pan in order to catch the fluid.
3. Loosen the bottom pan bolts. Drain the fluid in the pan. Wipe any fluid residue from the bottom pan.
4. Remove the bottom pan bolts, pan, and seal. DO NOT discard the seal, it is reusable.
5. Remove the left scavenger screen (larger one).



6. Remove the case plug (1) to drain fluid from the side cover.
7. Re-install the case plug.
8. Re-install the left scavenger screen.
9. Re-install the bottom pan, seal, and bolts. Finger-tighten the bolts.



10. Tighten the pan bolts 3 times to the proper specification, in the sequence shown:

•	Tighten the pan bolts to 3 N·m(27 lb in).

•	Tighten the pan bolts to 6 N·m(53 lb in).

•	Tighten the pan bolts to 12 N·m(106 lb in).

11. Lower the vehicle.
12. Open hood.
13. Remove the 8 retainers and the radiator support sight shield.
14. Remove the upper transaxle oil cooler pipe retaining bolt from the radiator fan shroud.
15. Disconnect the upper transaxle oil cooler pipe from the radiator using J 41623-B. Plug the cooler line.
16. Install the provided cooler line to the radiator quick connect where the previous cooler line was disconnected.
17. Connect the provided hose to the other end of the cooler pipe and secure with provided clamp.
18. Obtain drain pan and secure other end of the hose to the drain pan.
19. Position the drain pan and hose so that it is visible from the driver’s seat.
20. Remove the transmission fluid level indicator. Add DEXRON VI transmission fluid until the level is in the cross-hatched area. Slight overfill is alright. Re-install the fluid level indicator.
21. Start the engine and let idle.
22. Transmission fluid will discharge into the drain pan. Allow fluid to flow until first sign of air bubbles or lack of fluid (approximately 1 minute).
23. Turn the engine off.
24. Repeat steps 20-23 three more times.
25. Disconnect the hose from the cooler pipe.
26. Remove the provided cooler line from the radiator upper quick connect.
27. Reconnect the upper transaxle oil cooler pipe to the radiator.
28. Reinstall the upper transaxle cooler pipe retaining bolt to the radiator fan shroud.
29. Install the radiator support sight shield and retainers.
30. Refill the transmission with DEXRON VI transmission fluid to the correct level.

•	Remove the fluid level indicator.

•	Add fluid to the level at which it just registers on the indicator.

•	Re-install the fluid level indicator.

•	Start the engine and operate the vehicle for 15 minutes or until the transmission fluid reaches an operating temperature of 82-93°C (180-200°F).

•	Park the vehicle on a level surface.

•	With your foot on the brake pedal, move the shifter lever through each gear range, pausing for about 3 seconds in each range. Then, position the shift lever in PARK (P).

•	Apply the parking brake and let the engine idle for 3 minutes.

•	Remove the transmission fluid level indicator, wipe the indicator clean, and reinsert the indicator. Give the indicator a full twist to close.

•	Wait 3 seconds and remove the indicator.

•	Read both sides of the indicator. The fluid must be within the hot cross-hatched area using the lowest level reading.

For vehicles repaired under this service update, use: