DCT transmission overheat?

[Gangplank]

Originally Posted by Mr Rooty Von Tooty

Your transmission is failing. What you are experiencing is the way cars or all things mechanical communicate their feelings about their conditions.

During this period of time, owners try to rationalize the situation that these warnings are flukes of ghostly bugs. Eventually they accept the inevitable and open their wallets.

The dealers on the other hand, do recognize these signs of failure and try to weasel out of any responsibility. This is when owners have to get hard nosed about these issues to prevent getting buggered!

Or it could be a sensor that is failing...

[Wolfie1]

Originally Posted by sometorque

Oh wow, your experience is quite different from mine.

To update, I have a sample of the fluid I sent off to Blackstone today (good timing on the bump). The fluid seemed quite clean, cleaner than most of the fluid sample pictures I've seen online for that matter. I did have the transmission adaptations reset about 2 months ago and the light has not come back since. This seemed to do the trick for a few of the m3 guys who were having the same issue.

I've never had the transmission go into limp mode over this for any extender period of time. Usually just a quick flicker of the light, and then off again for months at a time. Given that I've put 20k miles on the car since this this issue started and the random nature of it, contrary to the above post, I do suspect the trans reset may have done the trick.

Your case seems a bit different, especially with the car going into limp mode for an extended period of time. I'd definitely have a mechanic look it over. From my several visits to the dealership with my issue, the shop foreman told me the DCT boxes are very smart and will throw a specific code for the part that's failing. In my case, I was getting a simple generic "risk of trans overheating code".

Good luck with your car!

Yeah I have been taking it to the dealer. They have it right now. First they thought it could have been a bubble in the collant system. That did not work. Then possibly the fan but that seems to be working.

They are looking into my clutch temp now. I haven't been able to get it to stay on.

It just seems weird I was having zero issues until this software update...

[Yeineken]

Little off topic. But concerning overheating. Has anyone ever retrofitted the M3 DCT oil cooler over to a 1er?

[sometorque]

Originally Posted by Yeineken

Little off topic. But concerning overheating. Has anyone ever retrofitted the M3 DCT oil cooler over to a 1er?

I did some research on this, but not enough to know the logistics of this.

Light came back on yesterday twice after an easy highway drive. Car drives fine otherwise with no indication of anything being awry. First time in a few months. Thought I finally gotten this solved, but no dice. Been dealing with this issue for about 20k miles now.

Car has 92k miles on it. At this juncture, I'm preparing an exit plan to get rid of the car. I love this car, but not enough to spend 5-6k for a used dct box if it does fail.

[Yeineken]

Originally Posted by sometorque

I did some research on this, but not enough to know the logistics of this.

Light came back on yesterday twice after an easy highway drive. Car drives fine otherwise with no indication of anything being awry. First time in a few months. Thought I finally gotten this solved, but no dice. Been dealing with this issue for about 20k miles now.

Car has 92k miles on it. At this juncture, I'm preparing an exit plan to get rid of the car. I love this car, but not enough to spend 5-6k for a used dct box if it does fail.

Sorry to hear that man. I'm thinking about retrofitting the cooler but using the 1M / PPK 2 driver side radiator, but hooking up and flowing transmission fluid through it.

SSP makes a cooler kit. However it's in the $1k range. So figuring it out with the 1M radiator will be much cheaper.

[bung206]

So what came of this?

I've got a 2011 135i that first started with ABS faults. I scanned it and found a fault for front right wheel
Speed sensor. Live data was showing no speed from it. So I replaced it with a ATE OEM from Pelican Parts. Then the front left started playing up. Replaced that. Too. Now the rear right is playing up (wtf.)

I was suszpecting a faulty ABS Module that couldn't interpret wheel speed sensors. But then I started getting "transmission fault", and just a few minutes ago I got "transmission overheated".

I am not sure what to do now.

[desertman123]

Originally Posted by sometorque

...

Needless to say, I'm quite frustrated with the issue at this point. My SA and the shop foreman have both stated "these cars are built to be driven hard", but then blame the issue on hard driving. Admittedly, they did tell me the engineer BMW sent over couldn't find anything indicative of the transmission failing and simply said "it's doing it's job by going into limp mode". Short of dropping the box and opening it, there's no real way to know if it's failing or not.

...

My mom used to work with Siemens and another company that sold directly to BMW. She told me German companies love pulling the "working as designed" card.

Hope you get this resolved!

[bung206]

Mine is "resolved" now.

I had a faulty rear right wheel speed sensor that was sending data intermittently. A broken wheel speed sensor on the rear is a big deal for a car with a DCT gearbox. The gearbox ECU needs accurate wheel speeds to decide whether or shift or not and when to shift. When the wheeel speed data is not present or the ECU thinks it's implausible, it will attempt to read the wheel speed using the output shaft which is not accurate. This causes the box to shift conservatively (and slip the clutch a lot I'm guessing). So the gearbox was really overheating.

I identified and replaced the faulty wheel speed sensor and the fault has gone away completely and the gearbox has not overheated after over 300 miles of driving in all conditions (hard pulls, normal driving, heavy traffic driving and freeway cruising).

A relatively cheap fix at ~$40 per sensor from Pelican Parts (that is if you don't count my time in figuring out and confirming the diagnosis and worrying!)

[JDM_CL9]

Originally Posted by bung206

Mine is "resolved" now.

I had a faulty rear right wheel speed sensor that was sending data intermittently. A broken wheel speed sensor on the rear is a big deal for a car with a DCT gearbox. The gearbox ECU needs accurate wheel speeds to decide whether or shift or not and when to shift. When the wheeel speed data is not present or the ECU thinks it's implausible, it will attempt to read the wheel speed using the output shaft which is not accurate. This causes the box to shift conservatively (and slip the clutch a lot I'm guessing). So the gearbox was really overheating.

I identified and replaced the faulty wheel speed sensor and the fault has gone away completely and the gearbox has not overheated after over 300 miles of driving in all conditions (hard pulls, normal driving, heavy traffic driving and freeway cruising).

A relatively cheap fix at ~$40 per sensor from Pelican Parts (that is if you don't count my time in figuring out and confirming the diagnosis and worrying!)

Sorry to revive an old thread but I think I may be having the same problem.

Did you get any Fault Codes etc when you determined it was the Speed Sensor causing the issue?

[Mr Rooty Von Tooty]

Originally Posted by sometorque

I did some research on this, but not enough to know the logistics of this.

Light came back on yesterday twice after an easy highway drive. Car drives fine otherwise with no indication of anything being awry. First time in a few months. Thought I finally gotten this solved, but no dice. Been dealing with this issue for about 20k miles now.

Car has 92k miles on it. At this juncture, I'm preparing an exit plan to get rid of the car. I love this car, but not enough to spend 5-6k for a used dct box if it does fail.

BMW won't cover wear on the clutch of a manual transmission. The wear can be caused by abuse or just normal deterioration. However, a clutch can last a long time if the owner treats the transmission with care.

The OP is experiencing clutch wear in the DCT, and this wear is being accelerated by his driving style of hard pulls. What's so dumb about his behavior is he keeps repeating his hard driving every time the DCT warns him about how unhappy it is!

BMW isn't going to cover replacing worn clutch packs, because wear is directly related to mileage or driving style. It's a big mistake to think BMW are designed to take the continued abuse of a spirited driving style. They are like any other car longevity dependent upon the owner treatment.

I don't want to parse through all his posts, but he might be able to understand why his DCT behavior by comparing it to the behavior of a manual transmission with a slipping clutch.

I would bet the DCT will soon need to be reconditioned. As I understand it, BMW only does exchanges on these unit. Also an Indy won't be any help. The smart thing to do is to get rid of this car before the DCT totally fails.

[The Wind Breezes]

Interesting thread. Sometimes when I'm driving savagely the car will upshift early, usually from 2nd to 3rd gear around 4-5k after WOT shifting from 1st in sport. I have a welded rear diff which may be slightly confusing the trans controller but I've had this issue sporadically ever since I got the car. It doesn't seem to be directly related to heat, as it doesn't always happen when tracking although the trans definitely gets laggy after a few minutes of driving wide open.

[Mr Rooty Von Tooty]

What is especially irritating about threads like this one is the OP leaves us hanging. He doesn't have the courtesy to let us know the outcome of his problem.

When someone posts some issue they have, often many people will respond with a range of advice from terrible to wonderful. The very least the OP could do is to let us know how the problem was resolved or not. It might be helpful to others!

[Esteban]

Would like to know the outcome (if anything's changed) as well. On occasion after some hard pulls, I think I'm smelling that 'burning clutch' smell. Hope I'm mistaken. No warranty here.

[The Wind Breezes]

Originally Posted by Esteban

Would like to know the outcome (if anything's changed) as well. On occasion after some hard pulls, I think I'm smelling that 'burning clutch' smell. Hope I'm mistaken. No warranty here.

The clutch is a wet clutch and it's all sealed up in the tranny! You may well have clutch wear but you're probably smelling something else.

[Esteban]

Originally Posted by The Wind Breezes

The clutch is a wet clutch and it's all sealed up in the tranny! You may well have clutch wear but you're probably smelling something else.

Any idea what I may be smelling?

[The Wind Breezes]

Originally Posted by Esteban

Any idea what I may be smelling?

Probably your brakes and / or just general fluids and crap that got on the engine / exhaust / whatever and are being burned off. If you don't constantly drive the car hard it will stink whenever you do. The reason you can smell a dry clutch when they burn is they're actually vented to the atmosphere.

[sometorque]

Originally Posted by Mr Rooty Von Tooty

BMW won't cover wear on the clutch of a manual transmission. The wear can be caused by abuse or just normal deterioration. However, a clutch can last a long time if the owner treats the transmission with care.

The OP is experiencing clutch wear in the DCT, and this wear is being accelerated by his driving style of hard pulls. What's so dumb about his behavior is he keeps repeating his hard driving every time the DCT warns him about how unhappy it is!

BMW isn't going to cover replacing worn clutch packs, because wear is directly related to mileage or driving style. It's a big mistake to think BMW are designed to take the continued abuse of a spirited driving style. They are like any other car longevity dependent upon the owner treatment.

I don't want to parse through all his posts, but he might be able to understand why his DCT behavior by comparing it to the behavior of a manual transmission with a slipping clutch.

I would bet the DCT will soon need to be reconditioned. As I understand it, BMW only does exchanges on these unit. Also an Indy won't be any help. The smart thing to do is to get rid of this car before the DCT totally fails.

You obviously did not read any of my previous post, did you?

There is nothing inherently "dumb" about what I was doing. The issue was occurring with no rhyme or reason, often without issue for months at a time. Hard driving had no bearing on the issue, as it would happen when the car was cold and quite literally inching out of a parking spot after sitting for a few days.

Since i never did update from my last posts, the last time the car was there, they did look at the clutch packs and determined they were actually fine. They admitted to me they were stumped, but that due to the previous owners treatment of the car, that BMW NA would not honor a transmission replacement. Blackstone also received a sample of the DCT fluid, which passed with flying colors. On paper and according to the SA, shop foreman and the BMW engineer who all looked at the transmission, they could not find a single thing wrong with it. Unfortunately, because the previous owner beat on it, they had a cop-out to not warranty the transmission.

I know it's easy to just blame the owner because that's often the past of least resistance, but let's call a spade a spade here. The car was meticulously cared for, and even the dealership couldn't determine the cause. This shouldn't scare anyone from DCT ownership long-term. Unfortunately, mine just happened to be the anomaly.

I have since sold the car and purchased something else to serve daily driver duties.

[sometorque]

Originally Posted by Mr Rooty Von Tooty

What is especially irritating about threads like this one is the OP leaves us hanging. He doesn't have the courtesy to let us know the outcome of his problem.

When someone posts some issue they have, often many people will respond with a range of advice from terrible to wonderful. The very least the OP could do is to let us know how the problem was resolved or not. It might be helpful to others!

Excuse me? I've documented this issue extensively for others to read about! it's the reason why anytime it cropped up, i wrote exactly what had happened. This is a great community of 1 series enthusiasts, which is why i try to pop in as often as I can. However, since selling the car, I just haven't been able to pop in and update everyone. Jesus, are you always this much of a pompous ass?

I have since sold the car and purchased a Lexus is300 for daily driver duties. I did have a chat with the new owner. The car has seen track time since I sold it to him (I documented everything I knew about the car, including this). he serviced the DCT fluid and has not had a single issue with it. He's prepared for it to go eventually, but for now, all is well. Car just hit 100k miles a week ago and everything is in working order. I'm keeping my fingers crossed for him that it lasts a long time. I loved it dearly and will own another one some day.

[Esteban]

Originally Posted by sometorque

I have since sold the car and purchased something else to serve daily driver duties.

Out of curiosity, what'd you get to replace it, if you don't mind telling? Nevermind... I see you got a Lexus is300. Nice car. Congrats!

[sometorque]

Originally Posted by Esteban

Out of curiosity, what'd you get to replace it, if you don't mind telling? Nevermind... I see you got a Lexus is300. Nice car. Congrats!

Thanks! Really happy with it so far. It was a one owner 5 SPD LSD car. It's slow as all hell, but for weekday duties it does the job.


I'm in the market for an ls3 c6 Corvette for weekend fun

[Mr Rooty Von Tooty]

Originally Posted by sometorque

Thanks! Really happy with it so far. It was a one owner 5 SPD LSD car. It's slow as all hell, but for weekday duties it does the job.


I'm in the market for an ls3 c6 Corvette for weekend fun

You are full of shit. Of course the dealer was stumped. They didn't want to waste their time on your behalf diagnosing some problem either real or imaginary. They are always happy to diagnose something that will lead to an immediate repair, "We are so sorry fool, but we believe the DCT needs to be replaced. That'll be around $10,000 (chuckling under their breath)!"

And you sold the car for a Lexus? What you did was dump the car on some poor fool suspecting an expensive repair. Few people would go from a BMW 135i to a Lexus except for financial reason.

I get really tired of guys like you always rationalizing your behavior. I have had hundreds of business dealing with characters like you. The more BS you lay down the more transparent your basic dishonesty.

I hope Santa dump a couple of tons of coal on your driveway!

[WhatsADSM]

Originally Posted by Mr Rooty Von Tooty

You are full of shit. Of course the dealer was stumped. They didn't want to waste their time on your behalf diagnosing some problem either real or imaginary. They are always happy to diagnose something that will lead to an immediate repair, "We are so sorry fool, but we believe the DCT needs to be replaced. That'll be around $10,000 (chuckling under their breath)!"

And you sold the car for a Lexus? What you did was dump the car on some poor fool suspecting an expensive repair. Few people would go from a BMW 135i to a Lexus except for financial reason.

I get really tired of guys like you always rationalizing your behavior. I have had hundreds of business dealing with characters like you. The more BS you lay down the more transparent your basic dishonesty.

I hope Santa dump a couple of tons of coal on your driveway!

Why are you attacking him like this?

The OP has been very straight forward about everything, and quite frankly I believe the DCT (at least the clutches themselves) is fine. There is A LOT of data on these transmissions which shows they are actually pretty strong, and I don't believe for one second that an owner taking the car to redline (7000 rpm on a transmission that is RATED for 9000 RPM) a few times and doing some burnouts (where the clutch is 100% engaged) is going to really stress it that much. I would track my E90 M3 which included 20+ minutes of going to its 8000+ redline and shifting HARD (full throttle, flying around turns, on take of Pirelli slicks). It took everything in stride, not a single issue... and that is certainly the majority of the peoples' experience.

The reality is while the transmission is mechanically very stout, it is electro-mechanically very complex. So it seems pretty obvious to me here, that based on the conditions when the OPs car would throw the light, the duration of the light, cadence of incidents, and the way it behaves under all other conditions, that we are looking at a bad sensor (or poor wiring/grounding) causing the TCU to see an elevated temperature when no such thing actually existed. Unfortunately beyond looking for a wiring/grounding issue, it sounds like the various temp sensors in the DCT are non-serviceable and therefore it would likely end up needing an entire assembly anyways So I definitely wouldn't say this is a true DCT mechanical failure, I wouldn't say any of this was due to abuse, and most of all I certainly wouldn't attempt to burn the OP at the stake because of what he has posted here. He has done nothing wrong.

OP:
Best of luck to you, sorry you got bit by a bit of a weird DCT problem. In general the Getrag DCTs are very good transmissions, but like any complex electro-mechanical part they aren't perfect. Thanks for sharing your experience.