According to Technical Service Bulletin 03-14-8, the number one cause for repeat transmission repairs in Ford's 1996 Explorer centers around the transmission cooler system. In the 4R44E, 4R55E or 4R70W transmissions, contaminants from prior transmission problems can settle in the cooling system and then be reintroduced into the transmission after repairs have been performed. Normal service on the transmission includes replacing the fluid and filter, but if repeated transmission problems occur, have the transmission cooling system flushed with a heated cooler-line flusher to remove contaminants from the system.
Park the Explorer on firm, level ground. Apply the parking brake. Jack the SUV up and support it on jack stands.
Place a drain pan capable of holding at least a gallon of fluid under the transmission pan. The drain pan must be of a larger outside dimension than the transmission pan in order to capture all of the fluid. Wipe around the perimeter of the pan lip and transmission with a lint-free shop rag to remove loose road grime and grit that could contaminate the pan. Have spare rags handy.
Using a ratchet and socket, loosen all of the transmission pan bolts, about one-half to three-quarters of the way out. Do not remove any bolts all the way at this time.
Starting with the side of the pan that is farthest away from you, pull the pan down. Allow the fluid to spill over the lip of the pan away from your body and give it a few minutes to drain down. In the event that the pan remains stuck to the gasket, you may gently rap on the pan with a rubber or leather hammer to encourage it to break free. Use caution to not deform the pan while using the hammer, and avoid prying the pan off as this can deform the pan's sealing surface and cause a leak.
Begin removing the pan bolts, starting with the ones farthest away from you. Allow the pan to sag to pour off as much fluid as possible, then hold the pan in place against the transmission and remove the rest of the bolts all the way. Grasp the pan with both hands and lower it away from the transmission. As you lower it, be aware that sometimes the gasket will stick to the transmission and the pan unequally. This may cause you to tip and dump the pan when you are lowering it. Pour any remaining fluid out of the pan.
Remove the transmission pan gasket from the pan and transmission, using a gasket scraper. Be careful not to gouge the mating surfaces. Wipe up any gasket shavings with a clean, lint-free shop rag. Inspect the pan for metal shavings that may indicate a mechanical problem in the transmission, though metal salt is normal. Clean the transmission pan with a little solvent and a clean, lint-free rag to remove any residual sludge.
Pull the filter down from the transmission. Inspect the filter and transmission intake port for the filter seal and remove it. You may need to stick a finger or a ratchet extension into the intake port to remove the O-ring seal.
Lightly lube the O-ring seal on the new filter with clean ATF. Insert the filter tube into the transmission pickup port and ensure that the O-ring does not deform during installation. Push the filter fully into place on the transmission.
Place the new gasket on the transmission pan. Do not apply any sealant; this gasket must be applied clean and dry. With the pan still off the vehicle, stick a pan bolt through the pan holes at each corner until the threads engage in the gasket and any other places necessary to keep the gasket in place during installation. Hold the pan in position on the transmission, and start the bolts by hand until they are engaged. Install the remaining bolts and tighten them finger-tight. Torque the pan bolts to 71 to 119 inch-pounds, using a crisscross pattern. Don't overtighten the bolts -- they break easily.
Pull the transmission dipstick and install a clean funnel into the dipstick tube. Pour three quarts of Mercon Automatic Transmission Fluid into the transmission. Look under the vehicle and check for leaks around the transmission pan.
Lower the vehicle to the ground. Start the engine, put your foot on the brake and slowly cycle through the gears, pausing for a moment in each, then return it to Park. Allow the engine to reach full operating temperature. Check the transmission fluid level with the engine idling and the transmission in Park. Add fluid if necessary to reach the "Full Hot" mark. Do not overfill.
