Transmission fluid flush method. Help!

[bwinterroth]

I am looking to switch from regular ATF to synthetic. I have read in the forum about a dozen different methods to flush the ATF, but the one I found easiest was to drive your front wheels onto ramps and do the drop pan method and take the drain plug out of the torque converter. This will allow almost all of the ATF to drain out (~15 quarts). Replace the filter, bolt the pan back on and refill with the amount that was drained out. Sounds simple enough but is it safe to do it this way? I have a 4.0L SOHC in a 2000 XLS with 60K miles. The ATF was changed previously by Ford at 30K miles.

The original post was by 97blackX5.0.

"i just drop the pan and take the drainplug out of the torque converter with the front wheels on ramps... this gets all but about a quart of it including that which is in the cooler lines if you let it set overnight.... then i put it all back together and dump in 13 quarts of fresh mercon....i do change the filter also"

 

[Con Seann3ry]

subscribing, the method i've heard of is disconnecting the tranny cooler lines, running it until you fill up a quart or two, then adding two more quarts, the downside of this is that you never completely get out the old fluid and need to run a few extra quarts through it.

 

[aldive]

The only method to remove all ( well, almost all ) of the ATF is via a flush. Its so simple and takes so little time ....

 

[bwinterroth]

Aldive,

if you had any pitures to supplement your flushing method that would be great. Thanks

-Ben

 

[aldive]

Aldive,

if you had any pitures to supplement your flushing method that would be great. Thanks

-Ben

Sorry no pics.

 

[Con Seann3ry]

The only method to remove all ( well, almost all ) of the ATF is via a flush. Its so simple and takes so little time ....

I heard it's bad for higher mileage trannys.

 

[Rhett]

I heard it's bad for higher mileage trannys.

In my experience, if a flush causes tranny failure, then the transmission had something wrong with it to begin with.

If all you have is sludge and crust holding the parts in place, then that's not a healthy transmission to begin with.

 

[bwinterroth]

help from Aldive

So Al,

I was looking at your method in other threads and you say disconnect the "to transmission" tube from the auxillary tranmission filter. Since I don't have one of a secondary filter, which tube would I disconnect, the "from the radiator" or "to the radiator"? Also, which side would I disconnect to put a 6' extension on, the radiator end or the transmission end? What size tube did you use for the extension? and what did you use to plug the other end to stop ATF from coming out. Thanks and sorry for all the questions.

-Ben

 

[bwinterroth]

Tried to post a drawing of the transmission lines to and from main and auxillary radiators but I can't attach. Anyways, where do I disconnect the hoses to flush the ATF. I am thinking at the output of the auxillary radiator but not sure. Thanks for the input

-Ben

 

[aldive]

You can disconnect the lines to and from the aux cooler. I use 3/8" fuel line. I plug the unused line with a bolt.

Be sure to test the lines to see which one is flowing.

Good luck ......

 

[Lee S.]

This thread should help you out with the flow direction of the tranny fluid:

http://www.explorerforum.com/forums/showthread.php?t=129514

And yes, I would say that the best place would be the output of the aux tranny cooler.

Lee

 

[aldive]

While you have the tranny lines off, this is a great time to add an aux tranny filter.

 

[bwinterroth]

One more question: do i need to pump out 1 quart of ATF at a time or can I pump out 4 quarts and refill with 4 quarts and repeat this another 2 times? Thanks

 

[aldive]

One more question: do i need to pump out 1 quart of ATF at a time or can I pump out 4 quarts and refill with 4 quarts and repeat this another 2 times? Thanks

The first time I did it, I pumped out 1 and then shut down the truck and added 1 qt and so on.

Subsequest times I simply add new as the old is pumped out.

Good luck ....

 

[Rhett]

One more question: do i need to pump out 1 quart of ATF at a time or can I pump out 4 quarts and refill with 4 quarts and repeat this another 2 times? Thanks

I usually pump out 1 quart at a time. On my truck it takes about 7-8 seconds to pump out 1 quart, so it's FAST. Be ready if you do it that way.

I marked milk jugs with a marker, at 1 qt intervals. Ran the tranny fluid output line (from the aux cooler) to the jug. Ran the truck for 7-8 seconds, shut down. Fill via trans filler neck with a new quart. Repeat until the fluid coming out is a nice clean red color. (as opposed to rusty red or darker).

Took me about 15-16 quarts before it started coming out clean if I remember correctly. A word of advice: Use cheap tranny fluid for the first couple of quarts you pour in, as you'll probably end up pumping that new fluid out anyway. After the first 2-3 quarts, follow with the good stuff (AMSOIL, Mobil1, Royal P. or whatever you prefer.)

You could probably pump out 2 qts or even 4 qts at a time. Just be careful you don't overflow your milk jugs, ATF is messy to clean up. Each jug holds 4 quarts (1 gal).

 

[trucku]

can the return line into the tranny be used as my filler? I want to do a flush. I will take one line out to a gal jug and then can I use a funnel on the other line and pour in? Or does that line not go back into the pan?

 

[Glacier991]

I used clear turing and a 5 gal pail. I put a funnel into the trans fill tube and had quart markings on the 5 gallon pail. I had all my fluid uncapped. With a helper at the ignition, I had the vehicle started and and attempted to match the rate at which the fluid came out with my adding fluid back in - kind on the fly, if you will. Ultimately at about the half way mark I fell behind and had the helper stop the engine until I caught up. As I recall I ended up running around 12 or 13 quarts thru the system before it started to run clear - by having the clear tubing I could assess that the color of the "waste" fluid coming out was turning bright red and that therefor new fluid was coming out. The idea of clear tubing was not mine but I recommend it. I think I ended up running maybe 2 quarts more than the total capacity to attain a clean flush. Hope this helps.

ps. NO the return line cannot be used as the fill line. There is no suction.

 

[trucku]

Crap...that blows...I have no fill tube. I guess I can use the tranny's factory fill hole. But that is gonna be a pain. I wonder if there is a better way to fill my tranny while letting it drain out?

 

[FL Oil Guy]

1. Make sure the fluid is warm. Warm up the car so the transmission is at normal operating temperature. Pull the transmission dipstick (located near the firewall in most cars). Fresh fluid is translucent and cherry red. Some darkening is normal, but if it is reddish brown or mustard color and smells like burnt varnish, it is worn out.

2. Drain the fluid by loosening the pan. Select the correct filter replacement based on pan shape and prepare a large pan to catch the fluid. Then loosen each pan bolt a turn or two and loosen one corner more than rest. Drain mostly from this corner.

3. Finish removing the pan and any gasket material from the pan or case. Avoid scratching the metal and make sure the pan’s gasket surface isn’t bent or distorted.

4. Remove the old filter. Most transmission filters are held in place with a bolt or two, but some are held by a clip. Be careful to include O-Rings or other seals.

5. Install a new filter. Use the clips or bolts from the old filter. Be sure O-Rings, etc. are in place. If the filter has a long intake neck, gently push the neck into place without unseating the O-Ring.

6. Clean the pan thoroughly. Inspect the pan before cleaning. A small amount of fine grey clutch dust is normal. However, if you find metal shavings, there has been transmission damage. Clean the pan with solvent and wipe dry so there is no harmful residue.

7. Position gasket on pan. Some gaskets have four holes slightly smaller than the rest to allow four bolts through the pan and through these smaller holes to hold the gasket in place.

8. Hand tighten pan bolts in a criss-cross pattern. After that, use a torque wrench to tighten bolts to proper ft-lbs as per manufacturer.

9. Refill the transmission using only the amount shown as “refill capacity” in the owners manual using the type of fluid specified for the vehicle.

10. If doing only a partial fluid replacement, skip to instruction 12 below. If doing a complete fluid replacement, follow the steps in instruction 11.

11. You now have replaced the fluid in the pan. To replace the fluid in the torque converter and oil cooler also, follow these steps.

Step 1. Obtain the total system capacity of the vehicle from the manufacturer. Have this amount readily available.
Step 2. Disconnect the oil cooler line from the oil cooler. As you may not know which is the pressure side and which is the return side, have both directed so the stream of fluid will be directed toward a receptacle.
Step 3. With another person, be prepared to add ATF to the fill area as it is being pumped out of the oil cooler line.
Step 4. Start the engine, and as the old fluid is pumped out, add fresh fluid to the pan.
Step 5. When either the fluid color brightens or the total capacity has been replaced, shut the engine off and re-attach the oil cooler line. All fluids has now been changed.

12. Recheck the fluid level. With the car on level ground, set the parking brake and the transmission in “Park” or “Neutral.” Let the engine idle for a few minutes. Shift the transmission into different positions before returning the lever to “Park” or “Neutral.” Check the fluid level again and check for leaks.