Auto Trans Fluid Flow Question

[Ron-Indy]

On a Ford Taurus, if one was to drop the pan, change the filter, button things up and refill with new fluid, how long would it have to run in order to fully mix the new fluid with the old trapped fluid in that is in the torque convertor and cooler lines?

Curious as to whether a 2 or 4 minute run while on the lift is sufficient or whether the car actually has to be driven. Want to pull the mixed fluid out through the dipstick tube with a Vacula in order to further dilute the old with the new.

Also, does the torque converter drain to the input shaft when the pan is removed or stay fully loaded.

Thanks....

 

[Scooter]

If your goal is a do-it-yourself trans flush, I think you might find these instructions more effective http://www.amsoil.com/faqs/faq8.htm

One addition to these instructions. I pump out a known quantity of old fluid into a graduated container (I used 2 qts.) then shut off the engine. Add two quarts to the pan and then start the engine and pump out two more qts. of old ATF. I do this start and stop procedure to ensure that I can add fluid as fast as it is being pumped out. It prevents you from running the pump dry.

 

[MolaKule]

It would take about 30 seconds for the fluid to mix. There is a constant circulating of the fluid through the torque convertor, otherwise the fluid in the torque convertor would not be cooled.

 

[Ken2]

Many Ford transmissions have a drain plug to drain the torque converter...with the pan off, roll the engine with a wrench 'til the plug is accessible. I don't know which Ford transmissions have this tc drain and which don't. If it does have the drain, then all that doesn't get changed is the cooler and lines, and they can be blown out or opened at the cooler and drained.

I've used the pump two quarts, stop the engine, refill two quarts, etc. routine. It's tedious, but works well. For very small transmissions, pump one quart. To find the direction of ATF flow in the cooler lines, disconnect one line at the cooler, disable the engine, crank the engine, and note the flow direction at that disconnected line.


Ken

 

[Ron-Indy]

Thanks guys, I appreciate the link and comments.

Since the car is up there in years it makes me nervous to break a line open and face the possibility of the resultant leaks (and mess), so I used the dilution method rather than the cooler line pumping method. Ran the car forward and reverse on the lift for about 3 minutes or so after the filter change before pumping the fluid out and replacing it. I later thought perhaps I did it too soon hence my question.

On the Taurus, the torque converter is not visable, so no way to drain it. My old 1973 Mustang Mach I did have the convertor exposed and was drainable.

Thanks again.....

 

[Alex D]

The amsoil Flush proceedure is what I have used successfully with one alteration.

Before I drop the pan, I unhook the transmission cooler feed line (For cross flow radiators: on GM cars it is the top line in the radiator, on Fords mostly the bottom line in the radiator........go figure??) put a hose on it and start the car. Let the car run until the fluid starts sputtering out of the hose. This way you empty the transmission pan and pan removal can be done without any mess if it does not have a drain plug. Don't do this and you will take a nice bath in ATF, trust me. On my 4L60E Vette transmission I was able to remove 7 quarts this easy way before I dropped the pan and it had only a few ounces fluid left inside. I didn't spill a drop taking the pan off.