Can someone explain to me the way to flush all the fluid out ot the transmission???
Here is what I know. To do the filter by dropping the pan, disconnecting the return line , run the engine until the return hose start to spurting bubbles out.
Here is what I do not understand :
To pour the same amount of ATF in to the dipstick fill hole , run the engine, repeat the process until about 13 or 14 Qts comes out ..
Wouldn't that be the same oil I just poured in to the dipstick will be coming out??? Dust that new oil prime the pump and force the old oil out???
can someone clarify this last step???

 

New fluid goes in the dipstick to the pan. The pick up pulls new fluid from the pan, pushing old fluid out the return line. This method works great and is super easy. This is the method I use on my 02 F250 and 04 Expedition.

 

Thank you for the explanation, I was not sure how dumping new oil would pump out the old one from the torque converter.
I did it yesterday.
Got all the fluid out. 14Qts of synthetic in.
By the way the return line from the transmission is the one on the passenger side front of the truck coming out of the transmission cooler.

 

Not sure what year your vehicle is (or which engine/trans yours has), but the transmission cooler return tube runs from the cooler(s) to the passenger side REAR of the transmission on the 4R100, while the transmission cooler return tube is the upper tube of the two tubes connected to the passenger side front of the 4R70 transmission.

 

Correct, which is the passenger side of the cooler
2006 , 5.4