DIY: Changing M-DCT Fluid

dparm wrote  

Ronnydashore wrote

So are people changing the DCT filter as well?

Not seeing any mention of it. The filter is about $60 -- part number 28107842840. I plan to change it.

I had initially planned to change it but it's difficult because there are other parts of the DCT blocking the filter. It would be easy without the parts blocking it. I just left it especially after seeing how clean the oil was after 70k.

S65 Underdog wrote

I had initially planned to change it but it's difficult because there are other parts of the DCT blocking the filter. It would be easy without the parts blocking it. I just left it especially after seeing how clean the oil was after 70k.

It's right on the side of the trans. Are you sure you weren't confusing it with something else? My shop had no problem with it.

dparm wrote

It's right on the side of the trans. Are you sure you weren't confusing it with something else? My shop had no problem with it.

Well either your shop took in my opinion a great deal of time or lied to you (I am guessing the second). Since I have time I will give a more detailed explanation to you of my DIY experience compared to a "my shop had no problem, are you confused" post.

Image A:



Image A: Number eight on this image shows you the location of the filter. The filter has a circle cover with a circle retaining pin to secure the filter cap.

Image B:



Image B: Shows the filter blocked by what seems to be lines connected to the DCT's pump system.

Also, when I was underneath my car I realized the difficulty of replacing the filter and it almost seems impossible without removing these lines (I am sure you can tell) and I couldn't find a point to remove these lines and honestly didn't want to go that far into it. Like I had said before in my last post, the fluid was so clean I wasn't even worried about the filter. I am talking so clean I could have poured it into bottles and sold it to you new none the wiser.

Interesting. I'd be surprised if they did lie to me, as they are pretty reputable bunch of guys.

dparm wrote

Interesting. I'd be surprised if they did lie to me, as they are pretty reputable bunch of guys.

They likely did not lie. You both are looking at the wrong filter.
Part #6 in the RealOEM diagram is the suction filter (before the pump) and the one that will have the major accumulation of wear material like friction material, bearings, bushings, and metal from the clutch steel plates.

Part #6 sits in the bottom on the oil pan and is the one you should change.

Part #8 is the pressure filter and is after the pump. The mechatronics module that controls the oil pressure for shifting is sensitive to particle contamination because there are small oil control orifices. IF the hydraulic pump were to self destruct the pressure filter might save the mechatronics module from needing replacement. To change the mechatronics module would probably require removing the transmission.

Hope this makes your filter change easier and helps at the parts counter getting the correct part.

kenwelch wrote

They likely did not lie. You both are looking at the wrong filter.
Part #6 in the RealOEM diagram is the suction filter (before the pump) and the one that will have the major accumulation of wear material like friction material, bearings, bushings, and metal from the clutch steel plates.

Part #6 sits in the bottom on the oil pan and is the one you should change.

Part #8 is the pressure filter and is after the pump. The mechatronics module that controls the oil pressure for shifting is sensitive to particle contamination because there are small oil control orifices. IF the hydraulic pump were to self destruct the pressure filter might save the mechatronics module from needing replacement. To change the mechatronics module would probably require removing the transmission.

Hope this makes your filter change easier and helps at the parts counter getting the correct part.

The filter that comes with the ECS kit is part #8.

part #8 is the second filter in the fluid path and will only get the trash that makes it through #6 the suction filter or pump wear.
I think they are providing the wrong part in the kit.

I have taught automatic transmissions for many years. The pickup filter in the bottom of the pan will get dirty first.

This is the link for the suction filter at ECS.
http://www.ecstuning.com/BMW-E92-M3-S65_4.0L/Drivetrain/DCT_Transmission/ES2228223/

kenwelch wrote

part #8 is the second filter in the fluid path and will only get the trash that makes it through #6 the suction filter or pump wear.
I think they are providing the wrong part in the kit.

I have taught automatic transmissions for many years. The pickup filter in the bottom of the pan will get dirty first.

This is the link for the suction filter at ECS.
http://www.ecstuning.com/BMW-E92-M3-S65_4.0L/Drivetrain/DCT_Transmission/ES2228223/

Do you have any information on this or are you just stating your a transmission master and just know it? I am not trying to be rude I just would like to see a little more then your words. A more detailed explanation and or a link to the information would be great.

I am starting to believe BMW with the lifetime fluid though. The stuff looked new at 68K.

S65 Underdog wrote

Do you have any information on this or are you just stating your a transmission master and just know it? I am not trying to be rude I just would like to see a little more then your words. A more detailed explanation and or a link to the information would be great.

I am starting to believe BMW with the lifetime fluid though. The stuff looked new at 68K.

I added the ECS link to the suction filter #6 in the illustration so others could see what it looks like and read the description.
It is called the suction filter because it filters the fluid on the inlet side of the pump. If you look at the photo in the ECS link and #6 in the RealOEM illustration you will see it fits in the bottom of the oil pan. It is the "pick-up" and filter for the pump that moves all of the hydraulic fluid. The fluid returns to the oil pan/sump after cooling, lubricating, and shift actuation by gravity. The returning fluid will have any contaminants like friction material, synchronizer particles, gear wear metals, bushing and bearing wear metal. The contaminants are FIRST filtered by the suction filter before entering the pump. Also read what ECS says about the suction filter on their site.

The filter that is #8 is called the pressure filter because it is after the pump and is used to protect the control unit. It's filtering is secondary to the #6 suction filter. This pressure filter makes sure that the expensive electronically controlled valve-body stays clean.

I have taught automatic transmissions and power train at the college level for more than 37 years, and just trying to put my comments in perspective. Many modern automatic transmissions use a secondary filter or screen to protect the control components. The reason I purchased my 2008 E92 M3 DCT is largely to the transmission and personal interest. I have studied the pictures, diagrams, and reviewed the training materials. I do not believe that Getrag would use a "window screen" material for the suction filter and allow all on the contaminates to be run through the pump only to be filtered by the pressure filter. That probably doesn't make sense to you either? or do you believe that the suction filter doesn't actually have filter material inside?

Did you pull the transmission pan when you did your fluid change?
With your "clean used fluid" you might only have a very limited amount of clutch debris in the pan. This is also true for many modern automatic transmissions.

If we can get someone to cut open their used suction filter and snap a few pictures we might get a true picture of the contamination collected.
Also take the diagram and pictures to a quality automatic transmission rebuilder and ask "which will get dirty first?"

S65 Underdog wrote

The stuff looked new at 68K.

Are you sure it hadn't been changed before?

This was mine at 75k, after I bought it, so no idea if it was changed, but judging from the color it wasn't. New is clear yellowish.

tdott wrote

Are you sure it hadn't been changed before?

This was mine at 75k, after I bought it, so no idea if it was changed, but judging from the color it wasn't. New is clear yellowish.

My fluid didn't look anything like that. It was clean and looked not much different from the new fluid after 70K on the fluid.

kenwelch wrote  

S65 Underdog wrote

Do you have any information on this or are you just stating your a transmission master and just know it? I am not trying to be rude I just would like to see a little more then your words. A more detailed explanation and or a link to the information would be great.

I am starting to believe BMW with the lifetime fluid though. The stuff looked new at 68K.

I added the ECS link to the suction filter #6 in the illustration so others could see what it looks like and read the description.
It is called the suction filter because it filters the fluid on the inlet side of the pump. If you look at the photo in the ECS link and #6 in the RealOEM illustration you will see it fits in the bottom of the oil pan. It is the "pick-up" and filter for the pump that moves all of the hydraulic fluid. The fluid returns to the oil pan/sump after cooling, lubricating, and shift actuation by gravity. The returning fluid will have any contaminants like friction material, synchronizer particles, gear wear metals, bushing and bearing wear metal. The contaminants are FIRST filtered by the suction filter before entering the pump. Also read what ECS says about the suction filter on their site.

The filter that is #8 is called the pressure filter because it is after the pump and is used to protect the control unit. It's filtering is secondary to the #6 suction filter. This pressure filter makes sure that the expensive electronically controlled valve-body stays clean.

I have taught automatic transmissions and power train at the college level for more than 37 years, and just trying to put my comments in perspective. Many modern automatic transmissions use a secondary filter or screen to protect the control components. The reason I purchased my 2008 E92 M3 DCT is largely to the transmission and personal interest. I have studied the pictures, diagrams, and reviewed the training materials. I do not believe that Getrag would use a "window screen" material for the suction filter and allow all on the contaminates to be run through the pump only to be filtered by the pressure filter. That probably doesn't make sense to you either? or do you believe that the suction filter doesn't actually have filter material inside?

Did you pull the transmission pan when you did your fluid change?
With your "clean used fluid" you might only have a very limited amount of clutch debris in the pan. This is also true for many modern automatic transmissions.

If we can get someone to cut open their used suction filter and snap a few pictures we might get a true picture of the contamination collected.
Also take the diagram and pictures to a quality automatic transmission rebuilder and ask "which will get dirty first?"

Thanks for the detailed information. If I would have known this I would have swapped it depending on difficulty to cut open the filter. I do agree that their is a filter in the suction filter one being the name and I can see the material in the picture.

Good stuff and thanks.

tdott wrote  

S65 Underdog wrote

The stuff looked new at 68K.

Are you sure it hadn't been changed before?

This was mine at 75k, after I bought it, so no idea if it was changed, but judging from the color it wasn't. New is clear yellowish.

I changed it for the first time.

S65 Underdog wrote

I changed it for the first time.

Are you the original owner?

tdott wrote

Are you the original owner?

No I am not the original owner. I did buy the car under warranty with the seals and plugs all being original.

I would say that 808Mguy also stated his fluid was great. You may want to point your fingers towards something else before asking me about my DCT. Especially with a cup of fluids like that. What would cause it to turn so dark in the first place. I am thinking serious wear.

I just read a thread about someones DCT fluid from Blackstone and they were amazed by the results. I would think they would say differently looking at that fluid you had. Even if someone had changed it. This would have been almost 40k miles ago. Clean fluid at that many miles would even be impressive.

DCT Blackstone report

http://www.m3post.com/forums/showthread.php?p=15563810#post15563810

S65 Underdog wrote

I would say that 808Mguy also stated his fluid was great. You may want to point your fingers towards something else before asking me about my DCT. Especially with a cup of fluids like that. What would cause it to turn so dark in the first place. I am thinking serious wear.

I was curious that's all, not pointing fingers, will look into doing another drain and fill as I have another 4 litres of fluid left and sending in a sample to blackstone.

tdott wrote

I was curious that's all, not pointing fingers, will look into doing another drain and fill as I have another 4 litres of fluid left and sending in a sample to blackstone.

I do not have "Blackstone" eyes, but the fluid in your picture looks overheated. Automatic transmission fluid will also change to a dark color with excessive heat. Changing the fluid again would be helpful from just looking at the photo. The Blackstone report could be helpful, but I'm not sure their report will provide data on friction material in the sample. It is good to see that they do check for antifreeze contamination. The DCT fluid and antifreeze share a cooler to assist with the warm-up of the transmission fluid. You picture does not look like antifreeze contamination.

You also might already know this, when "changing" the M-DCT fluid you are only getting about half of total capacity out. While expensive you might want to do another fluid change and include the suction filter. The suction filter is in the bottom of the transmission pan. If someone else changes the fluid/filter have them save the filter for your inspection. You will need to cut the filter open to get a real look at the "trash" that was captured. If you do it would be helpful to others to snap a few more pictures. Thanks for sharing the fluid sample pictures.

tdott wrote

I was curious that's all, not pointing fingers, will look into doing another drain and fill as I have another 4 litres of fluid left and sending in a sample to blackstone.

Sounds good! I am very tempted to reopen mine after kenwelch's post on the suction filter.

kenwelch wrote

I do not have "Blackstone" eyes, but the fluid in your picture looks overheated. Automatic transmission fluid will also change to a dark color with excessive heat. Changing the fluid again would be helpful from just looking at the photo. The Blackstone report could be helpful, but I'm not sure their report will provide data on friction material in the sample. It is good to see that they do check for antifreeze contamination. The DCT fluid and antifreeze share a cooler to assist with the warm-up of the transmission fluid. You picture does not look like antifreeze contamination.

You also might already know this, when "changing" the M-DCT fluid you are only getting about half of total capacity out. While expensive you might want to do another fluid change and include the suction filter. The suction filter is in the bottom of the transmission pan. If someone else changes the fluid/filter have them save the filter for your inspection. You will need to cut the filter open to get a real look at the "trash" that was captured. If you do it would be helpful to others to snap a few more pictures. Thanks for sharing the fluid sample pictures.

Even with removing the pan? I noticed after removal of the pan there was still some on the pan itself when removing it. Where else would there be some? Suction filter? Pressure filter? Anywhere else?

kenwelch wrote

You also might already know this, when "changing" the M-DCT fluid you are only getting about half of total capacity out. While expensive you might want to do another fluid change and include the suction filter. The suction filter is in the bottom of the transmission pan. If someone else changes the fluid/filter have them save the filter for your inspection. You will need to cut the filter open to get a real look at the "trash" that was captured. If you do it would be helpful to others to snap a few more pictures. Thanks for sharing the fluid sample pictures.

Those are great suggestions, thank you for your feedback, I will look into changing the filter this time as you are correct draining and filling doesn't get everything out. Will definitely post pictures when I have the filter apart.

I was also wondering if Canadian Climate would have been a factor.

S65 Underdog wrote

Where else would there be some? Suction filter? Pressure filter? Anywhere else?

My guess would be the lines and cooler.

tdott wrote

Those are great suggestions, thank you for your feedback, I will look into changing the filter this time as you are correct draining and filling doesn't get everything out. Will definitely post pictures when I have the filter apart.

I was also wondering if Canadian Climate would have been a factor.



My guess would be the lines and cooler.

I am really looking forward to you cutting that filter open!

S65 Underdog wrote

Sounds good! I am very tempted to reopen mine after kenwelch's post on the suction filter.


Even with removing the pan? I noticed after removal of the pan there was still some on the pan itself when removing it. Where else would there be some? Suction filter? Pressure filter? Anywhere else?

There will be additional fluid left in the:
coolers (above the transmission and in front),
cooler lines,
cooler thermostat,
pump,
dual clutch assembly,
Suction Filter,
Pressure filter and housing,
mechatronics control assembly (valve body),
lube spray bar for the gear set,
internal fluid passages,
clutch housing (if the vehicle is not level or slightly front up)
and the "nooks and crannies".

Unless you totally disassemble the transmission there will be some leftover fluid.

Visually inspecting the fluid is not going to tell you anything, short of there being some ridiculous contamination.

As I mentioned, my fluid was showing below-average particulate content at 51k: