To keep its transmission lubricated and operating within acceptable temperature limits, your car pumps transmission fluid through a hose, or line, to coils immersed in engine coolant inside the radiator. After circulating within these coils, the cooled fluid returns to the transmission through another line, and the cycle of fluid circulation continues. When these hoses or lines rupture, they require immediate attention. The do-it-yourself car owner can repair a damaged transmission hose in one hour with a few tools and materials.
Work on a level location on a hard surface such as concrete to support the weight of the car safely.
Place 4-by-4-inch wood blocks in the front and back of the rear wheels to prevent movement of the car while working.
Apply the parking brake of the car firmly. Put manual-transmission vehicles in neutral and automatic-transmission vehicles in the "Park" position.
Raise the car with an automobile jack to a high enough level for clearance to work beneath it. You'll perform this job in the area just behind the engine on the left side as viewed from the rear of the car. Place the jack at the front of the car or the left side, following the manufacturer’s recommendations.
Position jack stands directly under the frame on either side. Raise the upper telescopic part of each jack stand as close to the frame as possible, and secure it with a jack stand locking pin.
Lower the car slowly using the jack until it rests firmly on the two jack stands. Leave the jack in place, but do not rely on it to support the weight of the car. Check to ensure that the automobile sits securely on the jack stands.
Locate the two transmission hoses—the only lines that come out of the transmission and lead to the radiator.
Check along the length of each line until you find the rupture.
Clean the area on both sides and around the rupture thoroughly with 500-grit emery paper.
Cut the line on both sides of the rupture using the small tubing cutter.
Place the two compression fitting nuts over the ends of each of the transmission lines with the open threaded end facing toward the open end of the line and each other.
Slide the fitting sealing rings, or bite rings, onto each of the transmission lines.
Insert each end of the severed transmission lines into the body of the compression fitting. Push the lines into the compression fitting completely.
Tighten the nuts on the compression fitting using the adjustable wrench. Tighten each until you feel resistance, and then half a turn more.
Add the correct amount of the proper transmission fluid for the car using a funnel with an extended neck; follow the manufacturer’s recommendations.
Start the car and observe from the side for leaks. Do not go under the car while it runs. If a leak appears, shut the car off, tighten the fitting nuts one quarter of a turn each and recheck.
Raise the car slightly above the jack stands using the car jack.
Remove the jack stands, and lower the car to the ground.
Remove the jack and the wood blocks from the tires.
Recheck the transmission fluid level and add any further amount needed according to manufacturer specifications.
