A/T - 4L30-E - Removal/Replacement Precautions
Information IB05-05-S014Automatic Transmission Removal or Replacement Precautions
ISSUE DATE: DECEMBER 22, 2005
Affected Vehicles
All Isuzu Vehicles with 4L30-E Automatic Transmission
Service Information
The information in this bulletin must be followed when removing or replacing a transmission.
Transmission Flushing Procedure
Automatic transmission oil cooler flushing must be performed when an automatic transmission is removed for replacement or service. Automatic transmission flushing is required to remove contaminants and ensure proper flow of transmission fluid. The flushing procedure should be performed after the installation of the overhauled or replacement transmission. As part of the normal repair procedure for replacement of the automatic transmission, flushing the transmission cooler and associated lines/pipes must be performed.
To avoid a failure, the flushing procedure is required to insure that all debris and contaminants including metal, band material and burnt transmission fluid are removed prior to installation of the new transmission. The flushing procedure is part of the replacement procedure and if not properly performed, it will often result in premature failure of the replacement transmission.
The flushing procedure should be completed using a Transmission Cooling System Flusher (J- 45096 or equivalent) to ensure that all of the pipes and cooler are reverse flushed.
Follow the flushing procedure provided by the manufacturer of your flushing equipment. These procedures should be used as a standard practice after removing a defective transmission:
1. After removing the transmission, identify which line is the outlet and which line is the return line to the transmission cooler.
2. Attach the flush machine so that the flow of flush solution is the reverse direction of the transmission fluid flow. Be sure to only use approved Oil Cooler Flushing Fluid as directed by Transmission Cooling System Flusher J-45096 instructions.
3. After the flushing procedure is complete and the replacement transmission has been installed, a flow test must be completed.
Flow Test Procedures
Important: The Flow Test must be performed after the flush to ensure that all flushing solution and water is removed from the system.
1. Connect a hose from the transmission cooler return outlet side to an empty container capable of measuring fluid level as shown.
2. Confirm the transmission is filled with automatic transmission fluid. Refer to the Service Manual for the correct automatic transmission fluid capacity.
3. Start the engine with the transmission in Park and run for 30 seconds after fluid begins to flow from the discharge hose. A minimum of 1.9L (2 quarts) must discharge during these 30 seconds.
4. If the fluid flow meets or exceeds 1.9L (2 quarts) in 30 seconds the flow test is complete.
5. Reconnect all hoses to the transmission.
6. Check and adjust automatic transmission fluid level (refer to the Service Manual for proper procedure and capacity).
Alignment Dowel Pin Usage
When removing or replacing an engine or transmission, sometimes the alignment dowel pins fall out or remain in the transmission bell housing. Alignment dowel pins must be re-used or replaced before reinstalling the engine or transmission. Verify the alignment dowel pins are properly positioned as shown. Failure to use the alignment dowel pins correctly may cause damage to the transmission and/or flywheel.
Pilot Bushing
Before installation of the engine or transmission, verify the pilot bushing is present and in good condition. Replace if necessary.
Transmission Bolt Length and Location
When reinstalling a transmission verify the proper bolts are being used in the correct locations. The Bell Housing to Engine bolts vary in length and if installed in the incorrect location damage to the Engine Block may result.
Proper Fluid
The correct fluid to use in all Isuzu vehicles equipped with the 4L30E automatic transmissions is DEXRON III with a G-License Number (G-34318), Isuzu part number: 2-90531-815-0 or equivalent. Refer to IB03-05-S001 for additional information.
When checking for correct fluid level, follow the procedures in the Service Manual.
NOTE: Incorrect fluid or incorrect fluid level may cause shift complaints and/or transmission damage.
NOTE: Verify the transmission and engine mounts, driveline, and u-joints are in good working order. Replace if necessary.