Info - 4L30-E Automatic Transmission Service Policy Procedure

The limited on-vehicle repairs which may be performed are shown above. Parts needed for these repairs can be ordered from General Motors Service Parts Operations.

1. Record the customer concern on the repair order.
2. Use the Tech 2 scan tool to check for diagnostic trouble codes (DTC).

If there is a stored transmission code, refer to SI2000 or the printed Service Information for the specific DTC.

3. Test drive the vehicle. Monitor the powertrain with the Tech 2 or a suitable scan tool.
4. Were any DTCs set? If new DTCs were set, refer to SI2000 or the printed Service Information for the specific DTC. Correct all codes before continuing.
5. For a poor performance condition, verify engine performance. If engine performance is good, refer to the torque converter evaluation in SI2000 or the printed Service Information.
6. If all of the above steps do not lead to a concern correction and the transmission still does not function correctly, refer to SI2000 or the printed service information for further diagnosis information. If the diagnosis information determines that an internal component of the transmission needs to be serviced, do not disassemble the transmission; replace the transmission.

Notice: If the oil cooler and lines are not flushed and emptied of transmission fluid prior to the installation of a Goodwrench® SRTA, the transmission fluid level may be excessive and transmission damage could occur.

Oil cooler flushing and an oil cooler flow check must be performed whenever a transmission is removed for service. It is essential to flush the cooler prior to a Goodwrench® SRTA installation or when fluid contamination is suspected. Use Kent-Moore Tool J 35944-A and solvent J 35944-22 to flush the cooler. Instructions may be found in SI2000 and in the Service Manual in the On-Vehicle Service section. The time needed to flush the cooler is included in labor operation K7000 (Transmission Assembly Replace) for flushing of the cooler and the lines.

Checking of the fluid level is required after an SRTA installation or when any on-vehicle service procedure has been performed. The correct fluid level checking procedure is as follows:

1. Warm the transmission to normal operating temperature. This can be done two different ways.

•	Drive the vehicle 24 km (15 mi).

•	Run the engine until the transmission fluid temperature has reached 45-85°C  (113-185°F).

2. Raise the vehicle on a hoist and insure the vehicle is level.
3. Start the engine before removing the transmission oil level/fill plug.

Caution: 

•	The transmission fluid is now warm, 45-85°C (113-185°F). Take proper service precautions to avoid injury from warm fluid.

•	Do not turn the engine off with the fill plug removed. When the engine is shut off, hot fluid will be expelled from the fill plug opening and you may be injured by the hot fluid.

Important: The engine must be running when the transmission fluid fill plug is removed or excessive fluid loss will occur. Since the actual fluid level is unknown, have a container ready to capture any lost fluid and stand clear when removing the fill plug.

Important: To prevent fluid leaks and the need for repeat repairs, the fill plug seal must be replaced each time the fill plug is removed.

4. With the engine running and the transmission fluid at normal operating temperature, remove the transmission fill plug. The fluid level should be even with the bottom of the threaded opening in the transmission oil pan. If the level is low, add only enough Dexron®-III automatic transmission fluid to bring the fluid level to the bottom of the threaded opening in the transmission oil pan.
5. Reinstall the fill plug.

Tighten
Tighten the fill plug to 45 N·m(33 lb ft).

6. Inspect for external leaks. If a leak is found, refer to Automatic Transmission for the 4L30E, Fluid Leak Diagnosis, Document ID Number 405612, in SI2000. Refer to Diagnostic Information and Procedures, Fluid Leak Diagnosis, in the Automatic Transmission sub-section of the appropriate Service Manual.

A Goodwrench® SRTA (Service Replacement Transmission Assembly) should be used when any repair cannot be completed by the replacement of the parts shown in the previous portion of this bulletin.

Refer to the appropriate GMSPO Parts Catalog for the correct part numbers based on the application. The transmission identification information will assist in selecting the correct service replacement parts or the Goodwrench® Service Replacement Transmission Assembly (SRTA) unit to order from GMSPO.