Date registered: Dec 2005
Vehicle: W211 E320 Bluetec R129 SL500 - $1300 car ........ Ford F350 6l
Location: CA Bay Area
Mentioned: 9 Post(s)
Quoted: 1127 Post(s)
You should change ATF but not flush it.
I think you have 722 transmission?
But regardless what you have - dropping the pan, wiping it clean, filter/gasket change, new pilot bushing combined with replacing about 40% of ATF is perfectly safe and should be good enough for at least 50k.
If you want to go farther, you can buy about 12 l of ATF and after doing the above, disconnect cooler hose and start the engine for few seconds, catching old ATF at the hose.
Repeating refilling/draining 3-4 times will give you close to 100% fluid exchange in safe way.
Shops do power flushing without pan drop, what is very cheap for them, but can be very expensive for the owner, when dirt from bottom of the pan is pushed into transmission.
Last edited by Kajtek1; 12-16-2014 at 09:45 AM.