How to Install a Transmission Cooler in an F-250
- 1). Start a cool or cold engine and put the transmission in drive with your foot on the brake. Run the engine for ten seconds. Turn the engine off. Check the temperature of the two metal lines that run from the transmission to the radiator by touching the lines with your hand. The colder of the two lines is the return line.
- 2). Lubricate the ends of the hose from the installation kit with some transmission fluid. Slide two of the included clamps onto the hose. Press the hose ends onto the cooler tube fittings, forming a loop. Slide a clamp to within 1/4-inch of each end of the hose. Tighten the clamps with a screwdriver. Don't over-tighten; the hose ends should not bulge out beneath the clamp.
- 3). Decide on a location for the auxiliary cooler. Position the new cooler in front of the air conditioning condenser if possible, with the fittings pointing up or to the sides rather than down. Mount the cooler in the desired location using the hardware supplied by the manufacturer.
- 4). Disconnect the transmission return line from the radiator. Avoid damage to the line by using one wrench to loosen the line fitting while holding the radiator fitting with another wrench. Install the appropriate adapter onto the radiator fitting, again using two wrenches.
- 5). Route the loop of hose from the cooler to the radiator adapter. Cut the hose to length using a utility knife. Slide a hose clamp onto each end of the hose. If the cooler is mounted with the fittings on the side, select the hose coming from the bottom of the new cooler and press the end onto the adapter. Move the clamp to within 1/4-inch of the end and tighten. Attach the other hose end to the transmission return line and tighten the clamp.
- 6). Start the engine and check for leaks. Run the engine for two minutes. Feel the cooler lines to make sure both are warm, indicating fluid is flowing properly. Check the transmission fluid level and add fluid if necessary.
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