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For 1990-2009 cars only

Automatic Transmission Fluid Leaks

Condition

Action

Automatic transmission fluid (ATF) leaks from automatic transmission vent assembly (815)

Transmission unit overfilled with automatic transmission fluid (ATF).

Perform a fluid fill level inspection and if needed, drain ATF as needed to obtain the correct fill level.

ATF fill level is high due to engine coolant contamination

ATF level is high due to contamination resulting from mixing with engine coolant. Verify that the ATF is the correct color and does not smell burnt. If ATF is contaminated with engine coolant refer to contaminated ATF concern and correct as needed.

    • Automatic transmission vent assembly (815) is not installed, damaged or restricted
    • Vent hose (814) not secure, not installed, restricted or damaged
    • Vent pipe (812) not secure, not installed, restricted or damaged
    • Vent hose clips (813) not installed

Inspect and correct as needed. Verify that the unit has the correct ATF level after repair(s) are completed.

Fluid leak from between the engine and transmission assembly area

    • Engine rear main seal concern
    • Engine oil pan and or gasket concern
    • Engine intake manifold or gasket concern
    • Engine valve cover concern
    • Transmission torque converter (1) weld or seam issue
    • Transmission fluid pump body seal (200) worn and or damaged or not installed
    • Transmission fluid pump O-ring seal (206) not installed or damaged during installation

Add fluorescent oil dye to both the engine oil and the ATF. Inspect with a 16296 Black Light Leak Detection Lamp to aid in pinpointing the exact area of concern. Correct as needed.

Torque converter housing assembly (10)

Front differential carrier seal assembly (800)

Inspect the front differential carrier seal assembly (800) for not being installed, worn and or damaged. Correct as needed.

Front differential carrier seal (800) to torque converter housing (10) internal bore concern

Inspect the front differential carrier seal (800) to torque converter housing (10) internal bore for signs of physical damage and or oversize bore. If unable to repair, replace the torque converter housing assembly (801).

Manual shaft detent lever assembly (710) to automatic transmission case assembly (17)

Manual shift shaft seal assembly (713)

Inspect the manual shift shaft seal assembly (713) for signs for physical damage or improper installation or not being installed. Correct as needed.

Automatic transmission case assembly (17) manual shift shaft bore

Inspect automatic transmission case assembly (17) internal bore for proper finish and size. If damaged, replace the automatic transmission case assembly (17).

Input speed sensor (71) and/or output speed sensor (62) assembly to automatic transmission case assembly (17)

Sensor O-ring seal (63) or (71) not installed or sealing surface damaged

Inspect sensor O-ring sealing surface and replace if damaged or in question.

Automatic transmission case assembly (17) speed sensor internal bore

Inspect automatic transmission case assembly (17) internal bore for proper finish and size. If damaged, replace the automatic transmission case assembly (17).

Torque converter housing assembly (10) to transmission case assembly (17)

Lack of sealant

Add fluorescent oil dye to the ATF. Inspect with a 16296 to aid in pinpointing the exact area of concern. Correct as needed.

Torque converter housing assembly (801)

Inspect the torque converter housing assembly (801) sealing surface. If the sealing surface is not repairable, replace the torque converter housing assembly (801).

Transmission case assembly (17) sealing surface damaged

Inspect the transmission case assembly (17) sealing surface. If the sealing surface is not repairable, replace the transmission case assembly (17).

Mounting bolts not torqued to the correct specification, cross-threaded or missing.

Verify that there are no damaged thread issues, coat the fastener threads with threadlocker 242 and torque to specification.

Control valve body cover (29) to automatic transmission case assembly (17)

Lack of sealant

Add fluorescent oil dye to the ATF. Inspect with a 16296 to aid in pinpointing the exact area of concern. Correct as needed.

Control valve body cover (29) sealing surface damaged

Inspect the control valve body cover (29) sealing surface. If the sealing surface is not repairable, replace the control valve body cover (29.

Transmission case assembly (17) sealing surface damaged

Inspect the transmission case assembly (17) sealing surface. If the sealing surface is not repairable, replace the transmission case assembly (17).

Mounting bolts not torqued to the correct specification, cross-threaded or missing.

Verify that there are no damaged thread issues, coat the fastener threads with threadlocker 242 and torque to specification.

Automatic transmission case cover and 1-2 reverse clutch assembly (19) to automatic transmission case assembly (17)

Lack of sealant

Add fluorescent oil dye to the ATF. Inspect with a 16296 to aid in pinpointing the exact area of concern. Correct as needed.

Automatic transmission case cover and 1-2 reverse clutch assembly (19) sealing surface damaged

Inspect the automatic transmission case cover and 1-2 reverse clutch assembly (19) sealing surface. If the sealing surface is not repairable, replace the automatic transmission case cover and 1-2 reverse clutch assembly (19).

Transmission case assembly (17) sealing surface damaged

Inspect the transmission case assembly (17) sealing surface. If the sealing surface is not repairable, replace the transmission case assembly (17).

Mounting bolts not torqued to the correct specification, cross-threaded or missing.

Verify that there are no damaged thread issues, coat the fastener threads with threadlocker 242 and torque to specification.

Fluid leaks from a casting

Torque converter housing assembly (10)

Porous casting or signs of physical damage, including sealing surfaces. Repair as necessary. If unable to perform an external case repair, then replace housing assembly as necessary.

Automatic transmission case assembly (17)

Automatic transmission case cover and 1-2 reverse clutch assembly (19)

Fluid leak from top of automatic transmission case area, near wiring harness

Transmission wiring harness pass-through connector O-ring seal (46)

Remove the control valve body cover (29) in order to inspect the transmission wiring harness pass-through connector O-ring seal (46). Make sure the seal is installed and that there are no signs of damage.

Automatic transmission case assembly (17) wiring harness bore concern

Inspect the transmission case assembly (17) wiring harness pass-through connector internal bore for signs of damage or being oversize. Correct as needed.

Fluid leak from the oil cooler line area

Oil Cooler Line Seals (87)

    • Oil cooler lines not fully seated into seals
    • Oil cooler line retainer mounting bolts not torqued to the correct specification, cross-threaded or missing.
    • Internal bore concern, damaged or oversize within the transmission case assembly (17) oil cooler line seal bore.