HOW TO: change the automatic gerbox oil and flush on a 722.6 'box

Page may contain affiliate links. Please see terms for details.


Authorised Forum Sponsor
Feb 8, 2007
Portsmouth, Hampshire.
E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
Here is my how to on an ATF change on a 722.6 box.

There are loads of pics.

First pic of the car in question a E320 W210. Make sure the engine is hot. At least a 20 min road test

These are the parts needed. ATF 000 98921 03 10. Dipstick,filter pipe and sump seals.


Raise the car up and drain the fluid from the gearbox sump pan. Use a 5 mm Allen key and tap it in with a hammer. They can be very tight.

Let the old oil drain out. As you can see this ATF is pretty dirty. Remember to dispose of the oil in the correct manner. About 3.5L will drain from here.


Then undo the heat shield from the right hand side of the 'box.

The next step is to undo the sump pan retaining bolts. There are 6 of them. Again tap the torx socket in with a hammer. They bolts can be tight and have been known to snap off. Be very careful here. About 30% of the cars we do these bolts snap off. Only attempt it if you have the ability to drill them out if necessary.


Start with the front right bolt and unscrew it halfway. NOT fully.


The item above is called a pilot bushing and they often leak here. The part number is 203 540 02 53 for it.
Then undo all of the sump pan bolts. Remember to hammer the socket in.

Leaving the right front bolt in allows the fluid to drain from the drain hole until the sump is fulley drained.
Remove the old filter and install the new one. Give it a thump to loacte it. They tend to hang down a bit. This is normal. Note the loacting clip.

Last edited by a moderator:
The sump pan bolts have to be cleaned up on the wire wheel and the threads greased with heat resistant grease.


The pic is of some brake grease that I use for ceramic brakes.


This is a picture of the old bolts. They seize in so hence the reason for cleaning them

Clean the gearbox up where the gasket sits, of old ATF

Put the sump anp back up and make sure the gasket is secure on the pan. Hold the pan up and with the other hand use a brace to do up the bolt. Only do it up lightly at first. Put all 6 in and make sure the pan is straight and square to the box.

Torque all of the bolts up to 8NM


The next step is to fill the gearbox with 3L of fluid from the dipstick hole in the engine bay.




Push the retaining clip through the cap and discard. Remove the cap and start filling. A small funnel and pipe is what I use.

The next step is to flush the remaining oil out.

Firstly remove the banjo bolt from the left cooler pipe attached to the bell housing. You will need a 19mm socket and ratchet. Discard the two old seals. Oil will drip from here so have a drainer ready.



I have made a drain pipe from an old banjo bolt that I screw in the hole. This allows the fluid to drain into a container.




Whe the pipe is secured start the engine and leave running for 4 mins. This allows the torque converter to drain.
Connect the Star and bring up the gearbox temp.


Fill up the gearbox with another 3L of fluid. Put the Car in "D" with the parking brake on and allow to warm up. It can take a while! 80C is the temp to check the oil at.

Dip the sump with the dipstick with the gearbox in "N" or "P".



The highest level is the 80c one. It must be up there for the level to be correct.
You may need to top it up. You will need between 6-7L in total. Just add a small amount at a time.

Re-set the gearbox adaptations with the Star too. This will help you get smooth gear changes.

Users who are viewing this thread

Top Bottom