1981 240D auto transmission fluid change question - PeachParts Mercedes-Benz Forum

wilburtual · #1 08-12-2013, 11:47 PM

how much fluid is supposed to drain out of an 81 240D auto-transmission when I drop the pan and filter?

here's my story.. transmission started to flare when shifting, figured maybe low fluid level, so i check the dip stick, and its actually showing ABOVE the line when up to operating temp...? i know i've had to top off the fluid in the past every once and a while, so i can't see how there would all of the sudden be too much in there...? and it really feels like theres not enough when shifting.. so i go against the dipstick and add 1/2 qrt - and it helps, shifting is noticeably better. then a couple months later, same things starts to happen, gear shift slipping and dip stick still shows about an inch OVER the max line..

so i figure its well due for a fluid and filter change so i try it out (my first time changing this) I drop the pan and filter, let it drip til it stops, and put a new filter and gasket on. i did not drain the torque converter. only about 2 quarts drained out... is that way too little? i feel like i've read around here it should be more like 4? i check the dipstick after drained and no mark on it (duh) but then I add 1.5 quarts back in and check the dipstick- it shows ABOVE full again??

Am i missing something here...??? i feel like there isnt nearly enough fluid in there to be showing above the full line.. i don't want to under-fill and then drive on it... can the dipstick be messed up and showing the wrong level? it even shows too much when the engine is cold and on level surface....

thanks in advance for the help

vstech · #2 08-13-2013, 12:35 AM

it'll always read high cold, with the engine off. the 240 trans is very small, so 2 quarts may be correct for that one.
it's REALLY hard to get a correct reading on the transmission fluid level. you need a fully warmed up TRANSMISSION, that can take 30 minutes or more of driving to attain, then you have to be in park on a perfectly level spot. if your trunk is full, it'll throw off the reading.
if your motor mounts are worn it'll throw off the reading...
if the sunspot activity is high over the equator it'll throw off the reading... if you had burrito's for lunch it'll throw off the reading...

and, you may have the wrong dipstick in there...

Govert · #3 08-13-2013, 05:48 AM

The engine has to be running for the measurement.

Why didn't you drain the torque converter? It makes it easier to put in the required amount of fluid.

shertex · #4 08-13-2013, 06:02 AM

If you don't want to worry about sunspot activity, burritos, and the like, measure when cold (running, of course). There will be a cold level that corresponds to the hot level....on my cars, it is about 1/2" below the minimum mark.