Originally Posted by syfi

This is how you do it yourself. Only other way is with a flush machine @ the dealer or indie shop, which many have criticized for it's habit of dislodging chunks and clogging lines and valve bodies.. This requires 12-14 quarts of fluid in order to completely flush out the torque converter. Draining/flushing is done through the cooling return line from the tranny @ the radiator connector.

In a nut shell....

In order to perform a correct flush (Actual MB Procedure):

Remove the fill tube cap.
Remove and replace the pan filter
Fill pan with 5 liters of fluid.
Remove banjo bolt on fluid return (Pax side of transmission, route line to bucket)
Start car, count 3 liters of fluid, shut car off.
Add 3 liters of fluid.
Start car, count 3 liters of fluid, shut car off.
Add 3 liters of fluid.
Start car, count 3 liters of fluid, shut car off.
Re-install Banjo bolt.
Check sump level using dipstick tool (Factory tool), add as required with sump at 80C.

Thats a 100% fluid flush and should be accomplished every 30,000 miles on the 5 speed transmissions.

Anything less and you are just wasting fluid or delaying a worn out transmission valve controller.

Originally Posted by WD40

Instead of the "standard" ATF drain & fill where about 5 Liters (out of what, 8.5L?) are replaced I decided to take a shot at replacing 100% of the ATF as outlined in the procedure by SYFI in the 1st post of this thread.. I have 15 liters of ATF now, even though 14 should suffice because, why take a chance? And you can buy this German-made & Mercedes-approved ATF on EBAY for less than half what the genuine Mercedes fluid costs. I thought I'd have to soak the ATF-cooler-return-line in penetrating-fluid overnight but nope. You can see my flare-nut wrenches around the union of the return-line and it came apart very easily, no doubt because of my He-Man level of strength, right? Oh Hell, I might as well say the real reason... my superior manliness. There. It feels good to speak the truth at last! I left the drain-bolt off the pan so it can continue to drip until I can get back to it. The liters that came out still looked nice & red and didn't have any kind of odd smell. Here's some pictures to tickle your fancy...