What are the downsides of a DCT tune?

[Wally1552]

Hi
Been reading a lot of rave reviews about various dct tunes like alpine, bpm, ect. Seems like the benefits are smoother and quicker shifts. My issue with dct is it's very jerky when driving around town with the wife and kids especially in 1st and 2nd gear below 3k rpm. Am I the perfect customer for these tunes? My question is do these benefits come with any downsides to the life of the transmission? I'm not too technical but what are these tunes actually changing??. My thoughts are that BMW should have designed the software within specific tolerances and is it a good idea in the long run to mess with them?

[LMB335IS]

All DCT "tunes" are just different versions of BMW's own DCT software. The TCU of the DCT remain encrypted and until it's cracked there is no tuning available outside of BMW software.

Depending on the what version you're currently on, there may be updates available that address some issues and there's the GTS software that improves performance very nicely.

[SYT_Shadow]

You can get the stock DCT GTS or CRT file loaded to your car by anyone who does coding. Possibly in exchange of a few beers.

No downside that has come out. It's mechanically the same tranny as the GTS although that one has an extra quart of oil in the pan.

[Ab28]

First E9x, no tune.
Second E9x, tuned.

Don't know how I drove my first one without it. It's quicker, smoother, better around town and when you're pushing it.

Zero downsides.

Probably the best mod for the money.

[Wally1552]

Originally Posted by lat77

First E9x, no tune.
Second E9x, tuned.

Don't know how I drove my first one without it. It's quicker, smoother, better around town and when you're pushing it.

Zero downsides.

Probably the best mod for the money.

Which tune did you get are they all basically the same?

[Ab28]

Originally Posted by Wally1552

Which tune did you get are they all basically the same?

Alpine.

Get some coding done too

As far as I know they're all basically the same, and all better than stock.

[tdott]

Only down side is that you will always want to hear it downshift 😂

[amrazM]

Flash oem gts for free.


I believe Gts m3 has a different dct cooler and is overfilled one liter from the factory.

[dpilat8588]

When I got the DCT tune from Alpine, I also had him lower my launch control rpm to 3500 from 5000. Man, what a difference that makes! The DCT tune is a must have.

[amrazM]

Originally Posted by dpilat8588

When I got the DCT tune from Alpine, I also had him lower my launch control rpm to 3500 from 5000. Man, what a difference that makes! The DCT tune is a must have.

You don’t need a specific tune to do this, just use the speed adjustment switch.

[Wally1552]

Originally Posted by amrazM

Flash oem gts for free.


I believe Gts m3 has a different dct cooler and is overfilled one liter from the factory.

Where does one get this for free? And are ppl using the carly app to code it?

[amrazM]

Originally Posted by Wally1552

Where does one get this for free? And are ppl using the carly app to code it?

You need winkfp, if you have the Daten files for edibas it’s in there.

[LMB335IS]

What he said. The GTS flash lowers the beginning LC rpm to 3500, there's no additional coding needed for any of this. You need WinKFP loaded with the latest datens (part of BMW Standard Tools), a good DCAN cable, and a little knowledge. It takes 5-10 minutes to do, I've done it quite a few times for local guys.

[dpilat8588]

Originally Posted by amrazM

You don’t need a specific tune to do this, just use the speed adjustment switch.

What switch is used for this?

[Helmsman]

Wally, if you have a US car the OEM Euro DCT sw may do it for you, should you want to avoid to implement non OEM sw. Of some impossible to understand reason the US sw seem to result in a much more jerky operation.
As mentioned above, also worth checking the date of your current sw (dealer reading key fob, 10s job). I believe the latest DCT sw was released early 2011.

On OEM (Euro sw as here), box drives beautifully.

[dparm]

DCT tunes, in my experience, don't prevent things from being jerky. I don't know what Drivelogic mode you use, but I never found it to be jerky unless I was in S5 and really working the motor hard.

[dparm]

Originally Posted by dpilat8588

What switch is used for this?

The one on the left stalk.

[SYT_Shadow]

Originally Posted by LMB335IS

What he said. The GTS flash lowers the beginning LC rpm to 3500, there's no additional coding needed for any of this. You need WinKFP loaded with the latest datens (part of BMW Standard Tools), a good DCAN cable, and a little knowledge. It takes 5-10 minutes to do, I've done it quite a few times for local guys.

exactly, it is not rocket science.

There's a thread here where the full instructions are available

[Wally1552]

Yeah the more I read and speak to folks, I dont think a tune is going to solve what im primarily looking for which is to get rid of the jerk nature of the car. I'll check what the latest DCT software I have on the car. I noticed on the carfax (only had the car for a month now) the previous owner had a software update done at the dealer late last year 2018. Doesn't say what type of update though.

[kevin @ eas]

I have the Euro DCT flash and mine is still clunky at low speeds, especially when cold. High speed feels great and shifts quick. Starts out in S2 and I normally bump it up to s4 or s5 around town, seems like the higher settings shift less and feels better.

[wfdeacon88]

Originally Posted by kevin @ eas

I have the Euro DCT flash and mine is still clunky at low speeds, especially when cold. High speed feels great and shifts quick. Starts out in S2 and I normally bump it up to s4 or s5 around town, seems like the higher settings shift less and feels better.

I used to think the clunkiness was normal cold, then I was told I was way way low on DCT fluid. got that fixed and now mine doesn't have any clunk at all, even cold. it's as smooth as could be... you definitely know more about this than I do, but curious why my clunking is gone but others say they have it. (at 103K miles)

[tom @ eas]

I'm not aware of anyone doing DCT tuning, but can pretty much say that any DCT performance flash is simply a relabeled GTS file.

Back when we were tracking our M3s, we had better results (both shifting and performance) with the EU DCT flash rather than GTS, both on the 1/2 mile and racetrack.