M-DCT Transmission Fluid Changed and Tested

[Richard@M-World]

My NASA TTA track car has logged 30k miles and recently I changed out the Pentosin BMW-DCTF-1 fluid (PN 83222147477 20-litre can) for the first time as a preventive maintenance.

The fluid was then sent out to Blackstone Labs for analysis.

Just received the results back. This was Blackstone's first sample of the DCT fluid from an M car, so they could not make a comparison between my gearbox and others. However, they did observe that the "wear is so low that [they] doubt any mechanical problems."

My car has logged over 400 hot laps at my home track MSR Houston alone, so I would presume that for regular street use, the DCT fluid will last quite a long time.

I would still encourage more owners to send in their oil sample at different mileages (they only require 2-3 oz) so that we have a larger database to compare from.

The report is attached. The water mentioned was due to moisture caught during the collection process.

Cheers,
Richard@M-World

[Morning Hawk]

Great, thanks for this update. I've been skeptical about this "lifetime DCT fluid" for the M3 since I started following the GT-R forums and their DCT fluid maintenance schedules that are required on their DCT transmissions.

[///Montreal3]

Great info for the community. Most appreciated, thank you!

[Stainless 45]

Great info! Thanks for posting.

[aus]

As always, great work and much appreciated.

[SchnellM3]

Pretty amazing if you ask me. Especially since you are using your car as a track beast with that 400+ laps recorded that its not even showing any slight wear.

So the big topic here would be with your results would it be a safe conclusion that someone whose using a car as a daily or weekend car could expect this to hold up as BMW is claiming....

[j2m]

Awesome!! Thanks for sharing!

[Radiation Joe]

This is a transmission as apposed to motor. However, I'm impressed that nothing unusual showed up. I believe that if you have a good dct vs one with problems this will be the result. Keep in mind that even when I offered to pay for a fluid change in my dct, BMWUSA would not allow it.

Congrats on a clean bill of health.

[Justin(OKC)]

Thank you so much for posting this information. I'm trying to decide at what interval this should be changed. Good to know how things turned out with this sample. Was this the first time it was changed?

[Richard@M-World]

Originally Posted by Radiation Joe

This is a transmission as apposed to motor. However, I'm impressed that nothing unusual showed up. I believe that if you have a good dct vs one with problems this will be the result. Keep in mind that even when I offered to pay for a fluid change in my dct, BMWUSA would not allow it.

Congrats on a clean bill of health.

I've talked to a shop foreman at a local BMW dealership regarding changing the oil. I don't think BMW has a moratorium on changing DCT oil, but I think many dealerships are reluctant to do it because 1) BMW says it's lifetime, and 2) they do not want to take the risk on a gearbox that they rarely, if ever, work on.

Originally Posted by Justin(OKC)

Thank you so much for posting this information. I'm trying to decide at what interval this should be changed. Good to know how things turned out with this sample. Was this the first time it was changed?

Yes this was the first time. I would encourage everyone to at least send in a 2-3 oz sample to Blackstone to decide whether the oil should be changed. The oil is quite expensive, so doing such an analysis ($25) would be worth the money.

[OC3]

Had mine done - 2 months ago, at around 20,000 miles and around 400 hot laps.

[chmura]

Since you changed your DCT fluid you should post up a DIY of how you did it. This would be a huge benefit to people that want or are thinking about changing their DCT fluid.

[Mike van D]

Interesting, wonder if they do anything simular with the M3s currently being used at the Ring for Ring-Taxis. Couldn't find anything on it...they get punished daily.

[Richard@M-World]

Originally Posted by chmura

Since you changed your DCT fluid you should post up a DIY of how you did it. This would be a huge benefit to people that want or are thinking about changing their DCT fluid.

Will do. I took pictures during the process.

[Leonardo629]

It's not hard to grasp the idea, there's no combustion inside the DCT case, so the fluid supposedly will last a very very long time...I'm just wondering if there's some kind of filter inside the case

[BradfordSil]

Great info! Thanks for posting.

[Terraforce1]

Great to know, thanks

I would like to replace mine shortly, so perhaps a vid of how it was done would help

[mkoesel]

Excellent info, thanks for posting. Mine is almost at 60k now, and I admit that never having touched the DCT fluid does make me a little uneasy from time to time. Even though I suppose it is a relatively straightforward procedure, I am looking forward to seeing a DIY.

[calintexas]

Thanks for posting your results. It's great information.

It's possible that track use isn't the hardest service for the DCT. Heat and suspended contaminants should be the primary issues for the fluid. It seems like service with lots of clutching slipping such as stop and go traffic especially when the driver is using the transmission to hold the car on an upgrade or using the throttle and brake at the same time (like some people do an automatic in stop and go traffic) could be much harder on the fluid and clutches.

[chmura]

Originally Posted by Leonardo629

It's not hard to grasp the idea, there's no combustion inside the DCT case, so the fluid supposedly will last a very very long time...I'm just wondering if there's some kind of filter inside the case

That is true. In all my manual cars I changed the fluid every 100k+ miles and the fluid came out looking clean.

[klammer]

Great information Richard and can't wait to see the DIY. Plan on doing the change after this season and will plan on sending in my oil for analysis. Thx for the info

[///Mobbin]

Thanks for the info!