Here´s a PDF with the complete drain and refill procedure and how to adjust fluid level on the 6F50 and 6F55 transmissions. Mine is a 6F50 and 4.5 qts of refill will get the dipstick to read halfway, 4.6 qts will read pretty much a full transmission at the advised temperature (180-200 F) I always try to check the fluid as close as 190F as possible. I use ODBII bluetooth adapter and the Torque Pro App. Any more questions, feel free to ask.