I do the pump out method after the pan has been dropped, cleaned & the filter changed.

I then refill the pan with as much fluid as was removed, disonnect the cooler return line route it to my measured catch bucket & run the engine at 15 second cycles, as my tranny pumps 1 qt every 15 seconds.

I just don't like the idea of running the tranny pump dry. So I stop the engine every 15 seconds & pour in another qt.

About midway through, I do the shift through all the gears thing, to flush the valve body & clutches.

I do this 15 second start/stop thing, until the specified fill amount has removed, veified by the measured bucket.

This way I know Ive gotten most of the old fluid out of the valve body, clutches, torque converter & cooler.

If i've towed often I'll do the filter & full fluid change out every 20K miles.

After a full fluid change out I can feel the difference in the quality of the tranny shifts.

The fluid has always LOOKED ok, but I can tell by the difference in shift quality, it needed changing.

A complete fluid & filter change & pan gasket is WAY less costly than a breakdown tow, or a tranny rebuild, or a new tranny!!!!

I also do a power steerng system fluid flush & change at the same time!!!!
Don't forget, it's fluid gets tired too!!!

 

man-o-man, I've changed my tranny fluid just once in 24 years.

Of course, it's a T-18 Borgy.

And the same for the rear end; just once.

I've never changed or even flushed out my P/S system, ever.

Hmmmm, maybe I should, this summer.

 

sierraben get out and change your fluids!

 

Does anybody know if you can just attach a vacuum pump to the cooler line and evacuate the fluid that way?

If not, are there any instructions out there on how to flush a 5R55E trans w/o dropping the pan?

 

You won't get much out by using a vacuum pump.

Use the intructions in the Tech Articles ate FTE. I've used those instructions to change the fluid on a lot of cars and trucks, but never a 5R55E. It should work fine with some minor changes.