722.6 transmission fluid level
 

What I am looking for is a rough measurement of the fluid level when the vehicle is cold and on level ground, using the dipstick tool.

The internet has so many conflicting instructions on how to measure the fluid level when hot that I figured to approach it from a different perspective.

There has to be a ballpark measurement when the car is parked overnight and the transmission is cold.

PLEASE chime in, any replies will be greatly appreciated

Some amount of fluid will drain back from the torque converter, which is unpredictable. Hence all methods are while running. Also, cycling through all gears is important to ensure all clutch and brake actuators are full. I used to work for a transmission manufacturer, so I am very familiar with the reasoning.

Drive vehicle for 20-30 minutes. Stop and cycle through all gears including S and L, stopping in each gear for 2-3 seconds. When you're back in park pull dipstick and wipe. Reinsert, pull again and check. If you need to add, do no more than a few oz at a time. Once you add, it gets a little tricky to check as the oil will obfuscate the reading. It is usually easier to drive a few more minutes to keep the temp up and then recheck.

If you follow this method you can get reliable readings. Don't overfill. Aerated fluid is bad and you'll get erratic shifting or flaring.

On the 722.6 you are supposed to read it at exactly 80 C with the engine running with the special stick.

Preferred method is to read the transmission codes with a computer to get the fluid temperature from the internal sensor.

A close alternate is to use an IR thermometer to get the pan temperature.

There were different control systems tied to the 722.6 transmission.

The W210 used a mechanical shift linkage that pulled the lever on the transmission for P-R-N-D and then the 4-3-2-1 was electronically communicated to the transmission. When you pull the handle to the left it decouples from the transmission lever and just actuates switches in the shifter. (This is why spilling a drink in the shifter kills the transmission computer on these cars.)

The W211 uses an all electronic shifter mechanism (at least my 2008 does since it has a 722.9, not 100% sure how the pre-2007s handled this).

The reason I bring this up is that it is not like the older 722.3 and 722.4 that were directly mechanically controlled from the shift lever and it’s not as easy as just shifting to the lower gears especially on a W211.

On a 210 you can force the lower gears by selecting the 4-3-2-1 manually on the shift lever.
On a 211 you’ll have to rock the shift lever side to side and watch the counter on the instrument cluster to ensure you’ve achieved all the gears.

Helpful tip.

There is a small plastic triangle on the bottom of the measuring tool.
It is to be gently inserted just to the point where you feel it touch the bottom.
You will be at the bottom of the fill tube.
You can push harder and push past that point into the pan and the tool will land on the bottom of the pan, you have gone too far!

Just insert till you gently feel it bottom out on the fill tube.

Get a good reading with the fluid at temperature. Let the car sit overnight then check it cold for your car’s cold baseline.

Sixto
98 E320s sedan and wagon
02 C320 wagon

My own DIY dipstick has a 25cm mark which I use for cold level check, Start the engine, let it idle, check the level, if its at the 25cm mark its good for driving, if you dont see anything, add till you get to the 25cm mark.

btw - this is only applicable if your ambient temperature is between 70~85F - if you are checking it when rain water is frozen and polar bears are around, it wont work.

Once your cold level is set, drive it around till the transmission is warmed up and check again.