DCT Leak Recurring Problem?

[rantarM3]

Unfortunately I found my DCT (32K miles) seeping fluid out through the mechatronics seal and possibly also the lower pan. It seems to be a relatively frequent issue with many cars and in many instances, is covered under warranty. What I have not been able to find much information on is whether this issue reoccurs on cars that have had the seals replaced once already.

Does anyone know if the seeping is caused by seal failure, loosening bolts, or some other cause? I have a hard time believing that the seals go bad so quickly and am thinking it may be attributable to the bolts working themselves loose over time, such that a periodic re-torque would prevent it in the future. I know that some believe that the lower DCT pan warps because it is plastic but the mechatronics cover is metal and would not seem prone to warping.

Lastly, has anyone tried to simply re-torque the bolts after discovering a leak and have good results?

[///M Power-Belgium]

It's a complete kit with seals , pan , bolts ,and of course the Pentosin , ect...
About re-torque the bolts I've never saw or heard of it was done .

[rantarM3]

Originally Posted by ///M Power-Belgium

It's a complete kit with seals , pan , bolts ,and of course the Pentosin , ect...
About re-torque the bolts I've never saw or heard of it was done .

I just can't believe that the seals on the mechatronics cover go bad so quickly. Upon inspection, the seal looks good, is pliable, and has no evidence of rot. The only way I could see the oil seeping out is if the bolts worked themselves loose over time. I don't want to have the transmission taken out to fix the seal only to be right back in the same situation 3 years from now.

[///M Power-Belgium]

Originally Posted by rantarM3

I just can't believe that the seals on the mechatronics cover go bad so quickly. Upon inspection, the seal looks good, is pliable, and has no evidence of rot. The only way I could see the oil seeping out is if the bolts worked themselves loose over time. I don't want to have the transmission taken out to fix the seal only to be right back in the same situation 3 years from now.

Maybe you can ask this at your BMW/Dealer and also about re-torque the bolts etc...
There is no need to pull the transmission for replacing the kit .
I'm also curious about re-torque the bolts....
And I had changed my Pentosin at 30K as precaution ,but there was no difference in feel shift from before and after .

[Helmsman]

As just coming out from a DCT fix (..+ a bit..), I learned that the box also can leak from the top, assumingly where the oil cooling pipes are attached. Don't know whether needed to fix the mechatronic side but for the top leak the box obviously have to come down. Goes from simple fix to quite major job so yes get it done while under warranty.

Good luck!

Ps. Min was at 20k miles. Will keep an eye but hope it wont come back.

[rantarM3]

Originally Posted by Helmsman

As just coming out from a DCT fix (..+ a bit..), I learned that the box also can leak from the top, assumingly where the oil cooling pipes are attached. Don't know whether needed to fix the mechatronic side but for the top leak the box obviously have to come down. Goes from simple fix to quite major job so yes get it done while under warranty.

Good luck!

Ps. Min was at 20k miles. Will keep an eye but hope it wont come back.

I saw you got your transmission replaced after the dealer filled it with the wrong oil. Good for you that they took care of their mistake!

I looked at the mechatronics cover and it's pretty tight in there; not sure if a tech can get a wrench in there to take the cover off and replace the seal. I'll take the car into the dealer within the next week or so.

[Rewted]

Just for the sake of learning something today.... what color is this fluid?

[rantarM3]

Originally Posted by tyrewt

Just for the sake of learning something today.... what color is this fluid?

I dabbed a little on a paper towel and it was clear. The color seems more like diff fluid than engine oil. It has the same translucency as hiney but is not quite ao golden and more towards the grey spectrum.

[Helmsman]

Originally Posted by rantarM3

I saw you got your transmission replaced after the dealer filled it with the wrong oil. Good for you that they took care of their mistake!

I looked at the mechatronics cover and it's pretty tight in there; not sure if a tech can get a wrench in there to take the cover off and replace the seal. I'll take the car into the dealer within the next week or so.

Yep, really tight, doubt its possible without dropping the box. Also, you sure it is the mech cover mate? When coming from the top I'd imaging its tricky to say?

[rantarM3]

Originally Posted by Helmsman

Yep, really tight, doubt its possible without dropping the box. Also, you sure it is the mech cover mate? When coming from the top I'd imaging its tricky to say?

I checked the source and it is definitely the mechatronics cove. There is no evidence of fluid coming from the top of the transmission, which I am glad for. This is pretty annoying but at least I should get a DCT fluid change under warranty (I wa planning to do it at the end of the year at my expense).

[rantarM3]

Took the car into the dealer and got it back today. I was told that the leak/seeping is not bad enough to warrant a repair. As the transmission housing goes through heating cooling cycles, it may allow fluid to come out. I understand the dealer's hands being tied by the repair BMW NA will authorize under warranty. So my gripe at this point is with BMW. Does anyone else think that for a high-end car, this resolution is not acceptable? It's just amazing that it is leaking/seeping but for BMW just not badly enough. I would also like to hear from any folks who do think BMW not wanting to fix the seal is acceptable.

[///M Power-Belgium]

Originally Posted by rantarM3

Took the car into the dealer and got it back today. I was told that the leak/seeping is not bad enough to warrant a repair. As the transmission housing goes through heating cooling cycles, it may allow fluid to come out. I understand the dealer's hands being tied by the repair BMW NA will authorize under warranty. So my gripe at this point is with BMW. Does anyone else think that for a high-end car, this resolution is not acceptable? It's just amazing that it is leaking/seeping but for BMW just not badly enough. I would also like to hear from any folks who do think BMW not wanting to fix the seal is acceptable.

Try another BMW/Dealer .
BTW....No matter what kind of leak...A leak is a leak , end of story !
Never saw a normal leak !

[SSJVegita]

does the leak every show on the pavement when parked or is there some plastic cover that it leaks on to? asking cuz mine never leaves and smudges when parked but maybe i need to jack it up and actually check for real

[MPowerZ32]

I just got my car back from the dealer. The vertical pan and gasket were replaced under warranty. In case this is helpful:



The parts are 1 and 2, part # 28607842855 and 28607842856. According to the SA, they have a special tool to service the side cover. They just had to partially dismount the transmission to get it to rotate.

[rantarM3]

Originally Posted by ///M Power-Belgium

Try another BMW/Dealer .
BTW....No matter what kind of leak...A leak is a leak , end of story !
Never saw a normal leak !

That's exactly what I think but could see BMW getting cheap on near end of warranty repairs. It just boggles the mind that they consider any loss of fluid normal at all.

Originally Posted by SSJVegita

does the leak every show on the pavement when parked or is there some plastic cover that it leaks on to? asking cuz mine never leaves and smudges when parked but maybe i need to jack it up and actually check for real

No. It is a super slow seeping that seems to have started relatively recently. It covers about 1/4 of the lower pan; it's pretty obvious that fluid is coming out.

Originally Posted by MPowerZ32

I just got my car back from the dealer. The vertical pan and gasket were replaced under warranty. In case this is helpful:



The parts are 1 and 2, part # 28607842855 and 28607842856. According to the SA, they have a special tool to service the side cover. They just had to partially dismount the transmission to get it to rotate.

I hate going to the dealer because the car always comes back with some random damage, not necessarily due to the dealer's fault. For example, I got the car back with some bird crap on the roof. It was there for 24 hours at most anf probably less. It actually etched the clearcoat. But I gues a try elsewhere is worthwhile. Thanks for the part numbers.

[Helmsman]

Hi Rantar,

I wouldn't give in, it's a leak which they obviously should cover. The argument "small leaks are fine, BMW designed that in" is simply wrong. And what says it doesn't increase ending up with a more costly project, obviously shorty after your warranty has ended up...

Go get'em mate!

[vastano]

I had a seepage issue last summer. They also replaced the pan and gasket. I was switching my exhaust a couple weeks back and low and behold if its not leaking/seeping again. I didnt look to see where the oil was coming from, but the transmission case had an oily residue and there was a lingering drip. Also, the felt cover showed signs of there being a leak.

[Helmsman]

Originally Posted by vastano

I had a seepage issue last summer. They also replaced the pan and gasket. I was switching my exhaust a couple weeks back and low and behold if its not leaking/seeping again. I didnt look to see where the oil was coming from, but the transmission case had an oily residue and there was a lingering drip. Also, the felt cover showed signs of there being a leak.

Oh no..! So I'll certainly keep an eagle eye on mine to going forward...

[bakaneul]

I recently found out also my dct is leaking too. I suspect that mine is leaking from the rubber gasket on the side of the mechatronics and oiling down to the pan on the bottom. Leak isn't super bad since I didn't see any oil residue on the plastic cover but I am thinking to take it to the dealership to fix it before my warranty expires.

[rantarM3]

Originally Posted by Helmsman

Hi Rantar,

I wouldn't give in, it's a leak which they obviously should cover. The argument "small leaks are fine, BMW designed that in" is simply wrong. And what says it doesn't increase ending up with a more costly project, obviously shorty after your warranty has ended up...

Go get'em mate!

I will take some photos and visit another dealer, or talk to BMW NA. If BMW NA's CEO had a "small" water leak in his house and the plumber said it was expected and OK, I doubt his reaction would be any different than ours.

Originally Posted by vastano

I had a seepage issue last summer. They also replaced the pan and gasket. I was switching my exhaust a couple weeks back and low and behold if its not leaking/seeping again. I didnt look to see where the oil was coming from, but the transmission case had an oily residue and there was a lingering drip. Also, the felt cover showed signs of there being a leak.

This is my primary concern, actually. Getting it fixed only for it to happen again in the near future. You should be covered under the 2 year warranty on parts/labor from the dealer, no?

They did not list new bolts in your work order? My SA told me the bolts were stretch one-time use bolts and that re-torquing could not be done. I had requested that they at least re-torque everything as the seeping could be due to loosening bolts.

I think it is quite amazing that something as simple as a transmission seal is problematic on these cars. With my MPE going bad (although replaced under warranty), a bad belt tensioner, and a leaky transmission in 30K, this is probably my last BMW. I put up with it on this car because it's just such an exhilarating car to drive.

I wonder if there are any aftermarket alternatives to fix this problem, such as better gaskets or covers that don't warp (if that's the cause).

Originally Posted by ///Mint

I recently found out also my dct is leaking too. I suspect that mine is leaking from the rubber gasket on the side of the mechatronics and oiling down to the pan on the bottom. Leak isn't super bad since I didn't see any oil residue on the plastic cover but I am thinking to take it to the dealership to fix it before my warranty expires.

That's pretty much exactly what mine looks like and they said "not enough of a leak" and on the work order actually wrote "no problem found operating to main spec."

[Helmsman]

Originally Posted by ///Mint

I recently found out also my dct is leaking too. I suspect that mine is leaking from the rubber gasket on the side of the mechatronics and oiling down to the pan on the bottom. Leak isn't super bad since I didn't see any oil residue on the plastic cover but I am thinking to take it to the dealership to fix it before my warranty expires.

Mint, the box look "mint" - mine was all dirty although 20k miles 2011 - what year and mileage is the car?

[bakaneul]

Originally Posted by Helmsman

Mint, the box look "mint" - mine was all dirty although 20k miles 2011 - what year and mileage is the car?

Yeah mine looked clean which I was pretty surprised. It is 2012 model with 20K miles on the clock. I wish I had proper tools to fix this myself but sadly there is no way I could drop the tranny down..