Reading the dipstick

A Ford E4OD full tranny, lines and torque converter flush is actually quite easy. Simply removing the oil from the pan is not enough and typically only removes only a little over 1/3 of the oil. To do a near full fluid change with out wasting any new fluid, All you need to do is remove the fluid intake line from the rear of the tranny. An 11mm or 13mm open end wrench is all you'll need to remove the line. You can buy a 7 dollar fluid hand pump from Walmart or anywhere that comes with a 6" 1/2" clear plastic hose, usually 3 feet on either side of the pump. It will fit snugly over the intake line; hose clamp it if it feels loose, mine wasn't necessary. Place the other end of the hose into a container, the old 4-5 qt tranny fluid container will work. You might need to clamp the hose to the container if it doesn't sit securely. Once secure, start your engine then monitor the fluid being pumped out of the converter. You will need to run the engine for 1-2 minutes or until you see air mixing in with the old fluid being pumped out. Once you begin to see air, turn engine off. You should have pumped and additional 5-7 qts out. Next, let the sit for ten minutes then, with your $7 pump, pump out the remaining fluid from the lines. You may have to let it sit several times before the fluid drips down and becomes pump able again but after about 30 minutes of repeating this you will have recovered another 2 qts of old fluid. All told I was able to remove 14qts of the 15.8 qts of old fluid, including that of which I siphoned from the pan (really no need to change trans filter unless over 100k miles). Next reattach your trans intake line then fill your pan with 8qts, turn on engine and let it run for one minute then turn off and add another three qts. Turn engine on again then with brake on, shift through all the gears several times then add the remainder of your fluid. Only replace the exact amount of fluid that you removed. After running engine for 10 - 15 minutes, allow it to sit for several hours then check dipstick and add any fluid if needed but never overfill.