DIY: Changing M-DCT Fluid

I realize that this is long overdue, but here it is!

Important

Let your car cool for an extended period of time (at least 4 hours depending on the ambient temperature) before starting the process. If the transmission's temperature is too high, an incorrect amount of fluid could be added.

Fluid needed

83 22 0 440 214 BMW DCTF-1 (1L)
83 22 2 147 477 BMW DCTF-1 (20L)

Special tools needed

Fluid pump


Thermometer/contact pyrometer


Procedure

1. Remove the protective cover under the transmission.


2. Drain fluid by removing the plastic plug near the front passenger side of the transmission. Fluid can be extremely HOT! If your car was just driven, I would suggest waiting a few hours before draining the oil.




3. Once the fluid drain stops, reinstall the plug. Torque to the suggested value listed on the plug.

4. Open the filling hole (red box). Using a fluid pump, add M-DCT oil into the transmission. I added about 3 quarts before fluid started to emerge from the filling hole.


5. Ensure that M-DCT fluid inside the transmission is below 90 deg. F. Then, close the filling hole.

6. Turn on your engine. In position P, maintain 2000 rpm for about 1 minute.

7. Reopen the filling hole and add additional fluid (about 2 quarts) until fluid starts to leak out from the hole again. This process must be completed while the transmission fluid temperature is below 104 deg. F.

8. Close the filling hole and reinstall any removed panels.

did your car drive any better once you did this?

Thanks for the info OP. So you added a total of roughly 5 quarts? Is the fill bolt the one with white paint marking alignment with the trans?

I assume you would only recommend doing this for those who are outside the warranty period?

that 20L bottle is expensive!

NICE write up...

leigh wrote

did your car drive any better once you did this?

No perceivable difference.

Porschefile wrote

Thanks for the info OP. So you added a total of roughly 5 quarts? Is the fill bolt the one with white paint marking alignment with the trans?

BMW lists the 'initial fill' at 7.8 liters. But when you do an oil change, not all the fluid drains out, so only about 5 liters/quarts can be added. I've performed this on two cars and had one checked by BMW to verify that the fluid level is correct.

Yes to your second question.

THE TECH wrote

I assume you would only recommend doing this for those who are outside the warranty period?

The oil change process is not detectable/traceable.

rzm3 wrote

The oil change process is not detectable/traceable.

So are those your marks on the trans and plug?

Also, doesn't it supposedly void the warranty by doing so whether it's deemed detectable or not?

I recall you had the fluid tested from your car (http://www.m3post.com/forums/showpost.php?p=11491049&postcount=1) and the fluid was found to be in very good condition with 30k miles. With that in mind, why did you change it on the second vehicle? Have you continued to get the fluid tested and if so, have you found a point (i.e., mileage) where the degradation is noticeable?

Anybody know somewhere to buy the stuff cheaply? I seem to remember somewhere selling it for $25-30/liter but can't find it now.

awesome write up! looks easy

rantarM3 wrote

I recall you had the fluid tested from your car (http://www.m3post.com/forums/showpost.php?p=11491049&postcount=1) and the fluid was found to be in very good condition with 30k miles. With that in mind, why did you change it on the second vehicle? Have you continued to get the fluid tested and if so, have you found a point (i.e., mileage) where the degradation is noticeable?

It was a vehicle with higher mileage. Customer was moving abroad where he would have limited access to BMW service/parts.

Porschefile wrote

Anybody know somewhere to buy the stuff cheaply? I seem to remember somewhere selling it for $25-30/liter but can't find it now.

Talk to your dealer. Some offer discounts for car clubs such as BMWCCA and Houston M Club.

This is pretty much the same procedure for changing the transmission fluid (partial change) in an X5, which is rated to 100,000 miles. Why the M3 DCT is "lifetime" while the X5 is 100k is beyond me.

Any suggestions as to when you think the fluid ought to be changed?

Also, could you elaborate a little on how you measured the fluid temprature? Is it as simple as inserting the sensor into the fill-opening?

Thanks for making this thread!

^Yes simply insert the sensor into the fill opening.

Porschefile wrote

Anybody know somewhere to buy the stuff cheaply? I seem to remember somewhere selling it for $25-30/liter but can't find it now.

Cheap DCT Fluid

bigjae1976 wrote

Cheap DCT Fluid

Thanks!

rzm3 wrote

No perceivable difference.



BMW lists the 'initial fill' at 7.8 liters. But when you do an oil change, not all the fluid drains out, so only about 5 liters/quarts can be added. I've performed this on two cars and had one checked by BMW to verify that the fluid level is correct.

Yes to your second question.



The oil change process is not detectable/traceable.

I thought I had read elsewhere that you had to run the DCT pump to drain more fluid and that was only something the dealer could do (but wouldn't since it's "lifetime"). Is this true or not necessary. I guess if the net yield was only 0.5L or less that I would skip, but do you know if that's needed or not?

VictorH wrote

I thought I had read elsewhere that you had to run the DCT pump to drain more fluid and that was only something the dealer could do (but wouldn't since it's "lifetime"). Is this true or not necessary. I guess if the net yield was only 0.5L or less that I would skip, but do you know if that's needed or not?

No I have not heard about this. Perhaps you are referring to the fact that when the engine starts, some of the fluid gets pumped into the cooler and that's why more can be added when that process starts?

Nice DIY. where is the fill hole located exactly?

VictorH wrote

I thought I had read elsewhere that you had to run the DCT pump to drain more fluid and that was only something the dealer could do (but wouldn't since it's "lifetime"). Is this true or not necessary. I guess if the net yield was only 0.5L or less that I would skip, but do you know if that's needed or not?

I do that in my automatic M3 (Mazda3!). I brim the tranny with fluid. Remove the tranny cooler return line and then turn on the car. Shift from P to D a couple of times and then the tranny pumps out the fluid trapped in the cooler line. That will drain 3 extra quarts of ATF. Note that I overfill the tranny because you do NOT want to run the transmission dry.

I would imagine that it would be a massive PIA to do it like that in the DCT. Pumping extra liters into the DCT would be tricky, time, consuming, and (if on jack stands) very tiring. If you get 5L of 7.8L by a simple drain and fill, that's good enough for me.

My Mazda takes 6 qts of ATF, 3 of which is in the cooler and lines. So its worth it and its easy to add extra ATF in the dipstick tube.

0-60Motorsports wrote

Nice DIY. where is the fill hole located exactly?

As OP said above, the fill hole is the bolt with the white paint marking alignment with the trans, shown in the last pic in the original post.

Thank you so much for this. Am planning on doing this during the winter as my car is beat pretty hard:respect: