4R70E/4R75E - Automatic Transaxle/Transmission

Leakage Inspection








NOTE: An ultraviolet light must be used to detect the fluorescent dye solution.

Dye-Lite(R) ATF/Power Steering Fluid Leak Detection Dye 164-R3701 (Rotunda) (specifically formulated for ATF) is used to detect a transmission fluid leak.
1. Add detection dye to the transmission fluid. Use one 30.0 mL (1 oz) of dye solution for every 3.8L (4 qt) of transmission fluid. Add any additional transmission fluid, designated for this transmission/transaxle, to bring the unit to the correct transmission fluid level.
2. Start and run the engine. Shift the transmission through all gears several times to make sure that the fluorescent dye has had time to circulate. Observe the back of the engine, cylinder block and the top of the converter housing part of the case for evidence of transmission fluid leakage. Turn off the engine.
3. Raise the vehicle on a hoist.

4. NOTE: The leak source will probably be above and/or forward of the actual leak indication, due to airflow and/or gravity.

Using an ultraviolet light, observe the transmission for possible leaks. Following the leak back to its source point, repair the leak as required.

External Fluid Leaks

External Fluid Leaks:

External Sealing

CAUTION: Do not try to stop a transmission fluid leak by increasing the torque beyond specifications. This may cause damage to the transmission case threads.

The transmission has the following parts to prevent external transmission fluid leakage:
^ Gaskets
^ Lip-type seals
^ O-ring seals
^ Seal rings
^ Seal grommets
^ Seal washers
^ Thread sealant

External Sealing

External Sealing (Part 1):

External Sealing (Part 2):

Fluid Leakage in Torque Converter Area
Leakage at the front of the transmission, as evidenced by fluid around the torque converter housing part of the case, may have several sources.

By careful observation, it is possible in many instances to pinpoint the source of the leak before removing the transmission from the vehicle.

The paths which the fluid takes to reach the bottom of the torque converter housing part of the case are shown in the illustration. The 5 numbers in the illustration correspond with the 5 flow path steps.