An automatic transmission in a vehicle pumps fluid through pressure lines to cooling tubes inside the vehicle’s radiator. The fluid is returned to the transmission for use in its operation, then is pumped back to the radiator and the cycle continues. When repairs necessitate the removal of the radiator from the vehicle, the transmission cooling lines should be removed in the radiator shop. The work involved in removing the transmission lines can be done in 15 minutes with the proper tools and basic automotive knowledge.

Promoted by

Things You’ll Need

• Protective eyewear
• Wheel chocks
• Penetrating oil
• Two adjustable wrenches

• Splash pan
• Shop towels
• Oil-dry compound

• Remove the ignition key from the vehicle and place the gear selector in the “Park” position. Set the hand-brake and place wheel chocks on the rear wheels. Removing the key ensures that the engine will not be started while the work is being performed.

• Open the hood of the vehicle and locate the transmission line connections. Some makes and models have the lines at the lower section of the radiator facing the engine, and others are located on either side of the radiator. The lines will be at least 3/8-inches in diameter and near each other.

• Spray the connections with penetrating oil and allow the oil to work for 5 to 10 minutes. Place a splash pan in position to prevent oil spillage on the shop floor.

• Hold the brass union in place between the radiator socket and one of the transmission fitting nuts with an adjustable wrench. Place another adjustable wrench on the fitting nut and turn the nut in a counterclockwise direction.

• Slide the loosened nut back over the transmission line and pull the line away from the brass union. Allow any fluid drippings to fall into the splash pan. Use shop towels and oil-dry compound as needed.

• Repeat Steps 4 and 5 to remove the second transmission line.

Tips & Warnings

• Transmission lines may not always be connected to the radiator with a brass union. Some lines use male fittings that screw directly into the radiator socket. Still others may be connected to the radiator with flexible pressure hoses secured with worm-drive clamps.

• Follow radiator shop safety guidelines for proper disposal of old oil. Keep shop towels and rags in sealed metal containers marked for that purpose.
• Always wear protective eyewear.

Source