The Correct Way To Flush Any Transmission

I am posting this because I think that everyone here should know exactly the correct way to flush a transmission instead of
taking it to the so called shops that use the machines which will do more harm than good and also because I went round and round
with a moron from another forum who thinks that machine flushing is not bad on any transmission. This is for the 4th gen Transmissions
but can also be used for other auto transmissions.

Supplies needed:

Here's what you need:

==* 10qts trans fluid brand of your choice as long as it DEXTRON III
==* Tranny filling funnel
==* Tranny Pan Gasket 31397-80X01 (required if dropping the pan)
==* 19mm Tranny Drain Plug 31377-31X06 (optional, but might as well)
==* (21) Tranny Pan Bolts 31377-32X02 (required if dropping the pan) I reused mine
==* Tranny "Screen" inside transmission (some think it is a filter, but it is not.

Changing isn't necessary, but while you have the pan off, you might as well consider replacing) 31728-80X04





1. Drop trans. pan and clean debris off of bottom of pan and the 2 magnets.
2. Remove filter screen and clean with brake fluid. Then reinstall the screen
3. Install cleaned pan and torque all bolts according to manufacturer's specs.
4. Add 2 quarts of trans. fluid. Check owner manual for fluid type. we use Dextron III
5. Before starting engine, remove return line from radiator and install fitting with a hose on it.

Make sure the hose is long enough to reach in front of the car and clamp a bucket
Put that into a 5 gallon bucket to catch the trans. fluid. I use an old 5 gallon paint bucket as that is a very good visual.
6. Start engine and do not worry about tranny fluid spraying all over the place, it will be trickling out of that hose you put on.
Visually watch the bucket that is catching the old fluid and add Trans fluid accordingly.
7. A person will need around 10 quarts to do this, 2 for the initial fill and 8 for the flush. There are no such thing as shortcuts
in this way of doing the flush. Shortcuts are the machine flush that makes easy money for shops who do not change out the filters esp. stealerships.

Once the fluid turns bright red shut the car off. reattach the trans return line to radiator. Let the car sit for about 10 min and than check
the fluid level and top off if needed. Start the car and shift between all gears to get new fluid running each gear. YOUR DONE!!!

For all other transmissions, look up what it would take for a complete fill and not just a fluid and filter change and that is what you will
be buying in quarts of tranny fluid.

Photo was used from a fellow .org member

 

Thanks man looks great. I've used this method on several cars it really is the only way to go.

 

i pushed a slightly smaller clear hose into the line then put the line in my oil catch bucket like the one in the pic i can see when it turns red. also the hose fits right into the middle hole on the catch bucket ..no mess!

 

Thanks guy.... I've never had any trans issue since I've been doing it this way 2 cars ago. before then I sold cars because trans failure. Doing that trans flush machine and that 2 qt than drive and 2qt again then drive. I mean would you do that with your engine oil... nooooo you wouldn't, so why are people doing that with there trans.

 

thanks for the info.. sounds easy enough.. great directions. very helpful..

 

nice, i need to do this soon...good writeup.

 

Hey dude I re-used my pan bolts as well when I did my flush a couple years ago but now I am planning on doing another one, do you think I should re-use my bolts or get new ones this time? I never really understood why you would need to change them when dropping the pan.

 

First time I would use the same bolts but went you get into the second and third time look forward to having leaks. So I would suggest getting new bolts. You will be glad you did.

 

I am about to install my reman tranny on my car but, Is a reman better than a rebuild I am assuming so, I was wondering if I can reuse the old radiator because I dumped in lucas crap. Is there a way that I can flush out the oil cooler in the radiator. I want know what kind of a impact wrench can i use and tq limits.