Automatic Transmission Fluid Leaks

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Cause
DEFINITION: Automatic transmission fluid leaks that occur on the transmission.
Automatic Transmission Fluid Level	High fluid level - causing an oil leak at the vent assembly (37).
Automatic Transmission Fluid Condition	Contaminated with engine coolant, engine oil, brake fluid, etc. Oxidized and degraded - causing oil foaming and an oil leak at the vent assembly
Vent Assembly	The vent assembly (37) is plugged or damaged - causing high internal pressure inside the transmission and causing oil leakage at another component. Channel plate gasket (430) improperly torqued.
Oil Pan Assembly	The oil pan bolts and screws are loose, cross-threaded, or missing. The oil pan (24) is damaged. The oil pan gasket (25) is out of position or damaged.
Oil Filter and Seal Assembly	The oil filter assembly (100) is damaged. The oil filter seal assembly (101) is missing or damaged - causing oil foaming and an oil leak at the vent assembly.
Thermo Element Assembly	The thermo element plate pins (120, 123) are misadjusted. The thermo element (121) or thermo element plate (122) is out of position, missing, or damaged - causing a high fluid level in the oil pan, oil foaming, and an oil leak at the vent assembly (37).
Control Valve Body Cover Assembly	The control valve body cover bolts and screws (56, 57, 58) are loose, cross-threaded, or missing. The control valve body cover (53) is porous or damaged. The control valve body cover gaskets (54, 59) are out of position or damaged. The wiring harness assembly (224) is damaged or is leaking at the electrical connector terminals.
Front Wheel Drive Shaft Oil Seal Assemblies	The front wheel drive shaft oil seal assemblies (4, 409) are loose or damaged.
Forward Band Servo Assembly	The forward band servo cover bolts and screws (12) are loose, cross-threaded, or missing. The forward band servo cover (13) is porous or damaged. The forward band servo cover seal (14) is out of position or is damaged.
Reverse Band Servo Assembly	The reverse band servo cover retaining ring (39) is out of position or is damaged. The reverse band servo cover (40) is porous or is damaged. The forward band servo cover seal (14) is out of position or is damaged.
Oil Cooler Pipe Fitting Assemblies	The oil cooler pipe fitting assemblies (28, 29) are loose, cross-threaded, damaged, or are missing a sealer.
Case Extension Assembly	The case extension bolts and screws (5) are loose, cross-threaded, or are missing. The case extension assembly (6) is porous or damaged. The case extension seal (8) is out of position or is damaged. The front differential carrier bushing (7A) or the output shaft bearing assembly (7B) is worn or damaged. The case extension assembly (6) oil drain back holes are plugged or missing - causing repeat leaks at the right side front wheel drive shaft oil seal assembly (4).
Vehicle Speed Sensor Assembly	The vehicle speed sensor bolt or screw (9) is loose, cross-threaded, or missing. The vehicle speed sensor O-ring seal (11) is out of position or is damaged.
Oil Pressure Test Hole Plug	The oil pressure test hole plug (38) is loose, cross-threaded, damaged, or is missing a sealer.
Manual Shift Shaft Assembly	The manual shift shaft seal assembly (806) is out of position or is damaged. The manual shift shaft (807) sealing surface is damaged.
Park Pawl Actuator Guide Assembly	The park pawl actuator pin (808) is loose or missing. The park pawl actuator guide (809) is damaged. The park pawl actuator guide O-ring seal (810) is out of position, missing, or damaged.
Torque Converter Oil Seal Assembly	The torque converter oil seal assembly (525) is loose or damaged.
Drive Sprocket Support Assembly	The drive sprocket support (522) oil drain back holes are plugged or missing - causing repeat leaks at the torque converter oil seal assembly (525).
Case Assembly	The case assembly (3) is porous or damaged.