[E92Paul]

Hey guys, brand new to the forums and was wondering if any of you could give me some input on something. I searched around but could not really find anything that pertained to my situation so I thought I'd post a thread with the hopes of getting some better input.

I recently got a 2011 BMW 335is. I got it with 41,000 miles and have put 1,000 miles on it since buying. The car has the N54 engine and a DCT transmission.
Today, I was driving on the freeway going to the mall. I exited the freeway and entered the mall parking lot, and after a bit of low speed stop and go driving in the parking lot, a warning came up on the iDrive that went something like "Transmission temperature warning, please avoid stop and go movements and continue driving if possible." Then about 20 seconds later another warning came up this time "Transmission overheating, please press the "P" button on the gear selector and leave engine running for transmission to cool off." I'm paraphrasing but that's what it said more or less. So I parked the car and let it sit with the engine running for about 5 minutes before turning the engine off and going into the mall. About an hour and a half later I turn the car back on and drive home. The warnings never came back on the drive home and I even did a bit of stop and go low speed driving on my residential street to see if the warnings would come back, but they didn't. I should note that I did not drive the car hard at all that whole day. This is the first time this has happened since getting the car.

Does anyone know what might have caused this? What should I be checking/be worried about? Has anyone else encountered this issue? My car has BMS DCI and a stage 1 Cobb tune. Thanks in advance for any help you guys might be able to give me.

[STR8-6IX]

Originally Posted by E92Paul

Hey guys, brand new to the forums and was wondering if any of you could give me some input on something. I searched around but could not really find anything that pertained to my situation so I thought I'd post a thread with the hopes of getting some better input.

I recently got a 2011 BMW 335is. I got it with 41,000 miles and have put 1,000 miles on it since buying. The car has the N54 engine and a DCT transmission.
Today, I was driving on the freeway going to the mall. I exited the freeway and entered the mall parking lot, and after a bit of low speed stop and go driving in the parking lot, a warning came up on the iDrive that went something like "Transmission temperature warning, please avoid stop and go movements and continue driving if possible." Then about 20 seconds later another warning came up this time "Transmission overheating, please press the "P" button on the gear selector and leave engine running for transmission to cool off." I'm paraphrasing but that's what it said more or less. So I parked the car and let it sit with the engine running for about 5 minutes before turning the engine off and going into the mall. About an hour and a half later I turn the car back on and drive home. The warnings never came back on the drive home and I even did a bit of stop and go low speed driving on my residential street to see if the warnings would come back, but they didn't. I should note that I did not drive the car hard at all that whole day. This is the first time this has happened since getting the car.

Does anyone know what might have caused this? What should I be checking/be worried about? Has anyone else encountered this issue? My car has BMS DCI and a stage 1 Cobb tune. Thanks in advance for any help you guys might be able to give me.

you did more stop and go driving after receiving this error to see if you could replicate the same error message? that really doesnt sound like a good idea to me at all.

DCT's hate stop and go driving. I would either avoid this type of driving all together, or buy a second beater car to use for this type of driving.

[08njSTEP]

I would look into a fluid change on DCT. Also might get the pump checked. They go bad rather commonly. The DCT pump to be clear.

[E92Paul]

Originally Posted by 6IX-F10-N52

you did more stop and go driving after receiving this error to see if you could replicate the same error message? that really doesnt sound like a good idea to me at all.

DCT's hate stop and go driving. I would either avoid this type of driving all together, or buy a second beater car to use for this type of driving.

I drove the car more than a few times in Southern California stop and go traffic with no issues at all. I wanted to see if the warning would come back up again because that would indicate to me that something is definitely wrong/malfunctioning. That was my reasoning, at least.

[E92Paul]

Originally Posted by 08njSTEP

I would look into a fluid change on DCT. Also might get the pump checked. They go bad rather commonly. The DCT pump to be clear.

Are the pumps expensive to replace?

[STR8-6IX]

Originally Posted by E92Paul

I drove the car more than a few times in Southern California stop and go traffic with no issues at all. I wanted to see if the warning would come back up again because that would indicate to me that something is definitely wrong/malfunctioning. That was my reasoning, at least.

fair enough.

the only thing I can really think of is that your transmission was relying on all the fresh air on the highway to keep it cool and overheated once you got off the highway. once you restarted your car and continued to drive, I assume it figured out what it needs to do to keep cool.

This doesnt sound like a problem or something you need to fix/service. my opinion is that if this problem reoccurs, invest into a little manual shitbox for your stop/go driving duties - protect your DCT and leave it only for what it was designed to do.

[E92Paul]

Originally Posted by 6IX-F10-N52

fair enough.

the only thing I can really think of is that your transmission was relying on all the fresh air on the highway to keep it cool and overheated once you got off the highway. once you restarted your car and continued to drive, I assume it figured out what it needs to do to keep cool.

This doesnt sound like a problem or something you need to fix/service. my opinion is that if this problem reoccurs, invest into a little manual shitbox for your stop/go driving duties - protect your DCT and leave it only for what it was designed to do.

Thanks for the input!

[LMB335IS]

So much fail in this thread. If your DCT is overheating in stop and go traffic something is wrong. There is no such thing as the fresh air of the highway keeping it cool for you.

I've had mine since new, almost four yrs and it's been tuned since broken in and tuned aggressively (450-500whp range). I live in central FL and it's 85 degrees or higher at least 75% of the year. I've made multiple 1/4 and 1/2 miles runs, stop and go traffic for hrs, 1500 mile road trips, hrs blasting through mountain roads rowing through the gears and have NEVER gotten a temperature warning or any warning for that matter on my DCT. I guarantee I beat on mine more than you probably ever will. It's not something to blow off for very long, especially if it happens again. At the very least consider getting it serviced. A new replacement DCT runs $9-10k.

[STR8-6IX]

Originally Posted by LMB335IS

So much fail in this thread. If your DCT is overheating in stop and go traffic something is wrong. There is no such thing as the fresh air of the highway keeping it cool for you.

I've had mine since new, almost four yrs and it's been tuned since broken in and tuned aggressively (450-500whp range). I live in central FL and it's 85 degrees or higher at least 75% of the year. I've made multiple 1/4 and 1/2 miles runs, stop and go traffic for hrs, 1500 mile road trips, hrs blasting through mountain roads rowing through the gears and have NEVER gotten a temperature warning or any warning for that matter on my DCT. I guarantee I beat on mine more than you probably ever will. It's not something to blow off for very long, especially if it happens again. At the very least consider getting it serviced. A new replacement DCT runs $9-10k.

who the hell buys a DCT BMW? the actual fail in this case is that you guys all bought a BMW with the wrong transmission sitting behind the engine.

stop and go traffic will cause a DCT to heat differently VS molesting it on a canyon road with lots of air rushing through to keep it cool.

either dont use a god damn 335is DCT for stop and go traffic, or buy a manual transmission like you were supposed to.

god, you 335is "purists" had one job

[E92Paul]

Don't want to start a flame thread, just wanted some input on something I was concerned about.

[LMB335IS]

Originally Posted by 6IX-F10-N52

who the hell buys a DCT BMW? the actual fail in this case is that you guys all bought a BMW with the wrong transmission sitting behind the engine.

stop and go traffic will cause a DCT to heat differently VS molesting it on a canyon road with lots of air rushing through to keep it cool.

either dont use a god damn 335is DCT for stop and go traffic, or buy a manual transmission like you were supposed to.

god, you 335is "purists" had one job

Why comment on something you know absolutely nothing about and have absolutely zero experience with?

There are literally tens of thousands of DCT BMWs on the road. What you think is the right transmission doesn't mean dick to me or the OP.

Like I said, I have spent hrs at a time in stop and go traffic and it doesn't cause the trans to overheat. If it did it would be a engineering flaw and that flaw exists nowhere beside your mind. The DCT is a more efficient trans than an automatic. It was designed for every possible condition of any market BMW sells them in.

Please have a clue before you start handing out useless, bad advice.

[drunkenup]

Originally Posted by 6IX-F10-N52

who the hell buys a DCT BMW? the actual fail in this case is that you guys all bought a BMW with the wrong transmission sitting behind the engine.

stop and go traffic will cause a DCT to heat differently VS molesting it on a canyon road with lots of air rushing through to keep it cool.

either dont use a god damn 335is DCT for stop and go traffic, or buy a manual transmission like you were supposed to.

god, you 335is "purists" had one job

You seem to have a very tenuous idea about how cars work. There are tray panels and heat shielding covering almost every inch underneath the engine and transmission. Even if they were exposed do you really think the rush of air is going to transfer heat off of the metal casing?

Oil from the transmissions are carried through lines to a heat exchanger sink transfers heat to the coolant and radiator. That is how it is cooled. How do you criticize somebody for driving a automatic BMW from behind the wheel of a base F10?

[LMB335IS]

Originally Posted by E92Paul

Don't want to start a flame thread, just wanted some input on something I was concerned about.

I don't either and it's not. It's fact vs fiction. You are free to believe whatever you want. Feel free to PM me if you have questions.

[STR8-6IX]

Originally Posted by drunkenup

You seem to have a very tenuous idea about how cars work. There are tray panels and heat shielding covering almost every inch underneath the engine and transmission. Even if they were exposed do you really think the rush of air is going to transfer heat off of the metal casing?

Oil from the transmissions are carried through lines to a heat exchanger sink transfers heat to the coolant and radiator. That is how it is cooled. How do you criticize somebody for driving a automatic BMW from behind the wheel of a base F10?

transmission cooler. does your DCT not have a transmission cooler?

how else would rushing air somehow penetrate plastic and cool the god damn transmission?

[YasF80_SLO]

Originally Posted by LMB335IS

Like I said, I have spent hrs at a time in stop and go traffic and it doesn't cause the trans to overheat. If it did it would be a engineering flaw and that flaw exists nowhere beside your mind. The DCT is a more efficient trans than an automatic. It was designed for every possible condition of any market BMW sells them in.

I have driven plenty of DCT cars in heavy traffic and never had any issues with overheating, e9x M3 DCT, and F80 DCT, sure they smell like a brand new manual driver who cant use a clutch, but they sure dont overheat out of nowhere.

[maddmatth]

I wonder if you were forcing it to ride the clutch. If you crawl forward while partially on the brake to make it go slower than it's regular crawl speed, you make it ride the clutch (just like a manual). That'll generate heat and can wear down the clutch, try to avoid doing that.

Pretty much any situation where you'd have to ride the clutch in a manual, the DCT has to do the same. So just take that into account.
I've had mine in some stop-go traffic. I try to avoid following the habit auto drivers have where they crawl slowly. Rather wait for a decent gap and let the car move at it's own crawl pace until you need to stop.

[rsyed07]

^I agree, I usually wait for a decent gap before accelerating. I avoid creeping or crawling as much as possible in stop and go situations.

[remixaflip]

I am willing to bet that your transmission fluid is starting run low. I had to get my DCT trans serviced over the summer because the lower pan and side pan had a slow leak. You should not get any overheating in stop and go traffic. The only times I've got those warnings is when I did consecutive WOT pulls back to back.

If your trans continues to leak, eventually you trans will only be able to shift into a couple of gears and you'll end up limping along to a shop.

[Eddien123]

Originally Posted by E92Paul

Don't want to start a flame thread, just wanted some input on something I was concerned about.

Yeah people on here are real sensitive.

Here's my thinking. The car should not be having an issue with transmission temperature. I'm sure your driving style mimics that of many 335is owners on the forum here. Also, M3/4/5/6 owners with DCTs also drive in stop and go traffic. I mean for fuck sake a Hyundai volester has a DCT. If a DCT over heats in stop and go, a regular manual would as well so here's my conclusion and suggestion.

1. In my experience, BMWs love to throw codes once and never show them again. (This has happened to many people here including myself) so that could be it.

2. It could be a real problem that needs sorting out so my suggestion is to also ask the Z forums and M forums since both cars have DCT transmission options. If you're having an issue its possible they are as well.


But if you haven't seen the code reoccur more than once when driving in the same conditions then I'm sure it was a random glitch and shouldn't happen again.

[maddmatth]

I think the poster saying it could be low fluid, could very well be right. Recommend you get it checked for leaks before it gives you more headaches down the line. If you're able to lift the car and get under it, it won't be hard to pop off the under tray panels and get a good look at the trans. From there it should be fairly obvious if it's leaking.

[Jarrod]

Did you notice the engine temp when this happened? I believe the heat exchanger is not only there to cool the transmission but also warm it up when you first start driving - not sure if you've noticed but the wet clutches don't perform their best when the fluid is cold.

So I'm wondering aloud if for some reason (failing water pump, thermostat, radiator fan?) the engine was hot and perhaps pumping heat into the transmission via the exchanger (or cooling it less efficiently), and the added friction of stop and go driving put it over the edge. Maybe keep an eye on that.

As far as the "335is purist" comment above goes - blasting down a winding road, flapping through seven gears with 50ms shifts, perfect throttle blips, and both hands on the wheel is the way this car was meant to be enjoyed as far as I'm concerned. Not that I'd turn down a 6MT, but the notion that our Getrag gearbox is inferior is more than a bit ludicrous.

[mweisdorfer]

I'd change out the fluid and filter. Amsoil or redline make great ATF for your car. You can get a Transmission filter anywhere really. I wouldn't pay more than $125.00 for the pan filter.

Best way to get all the crap out of the torque converter is Buy like 5 gallons of ATF. You change the pan filter and fluid and then drive it for a week and drain and fill it again. Drive it for one more week and drain and fill it, for a total of 3 drain and fills including the initial drain and fill when you put a new pan filter in. This way you get 95% of all the old fluid out.

I'd change it and the pan filter every 50k.