DCT Clutch Wear

[fleainat]

Has anyone had any clutch wear issues with the DCTs?

I am in 100% city stop-and-go, so I have been using D1, which starts in second gear. In a true manual, second-gear starts and feathering the clutch results in clutch failure.

Does anyone know if this is similar in the DCT?

[WickedE93]

Good question, I'd like to know the answer as well. BTW why do you prefer D1/starting in second gear?

[SenorFunkyPants]

The only people I know of who have worn out DCT clutches are in supercharged cars and driven hard, stock cars are very robust. Replacement DCT clutch disk packs are available and shouldn't cost much more to replace than a clutch in an MT car.
I doubt using D1 would cause much of a problem long term unless you have the habit of using a lot of throttle to pull away, but you may want to consider using D2 instead.

[BrewRifle]

I don't know how you can drive in D1, you'll be in 7th gear by 35 MPH. I at least have to use D3 in any sort of traffic.

[jblaze21]

D1 seems excessive as it's meant for low traction situations like snow I believe, although I could be wrong.

Also I believe the DCT will have to slip the clutch a bit to get it going starting in second gear each time. I would not drive in D1 at all. D2 if anything or better yet, don't drive in D at all. I've never driven in D mode, just can't see the purpose stop and go or not.

[crypticc]

you wouldn't start a car in second gear every time with a real manual which would skip the clutch and could labour the engine, so why make the car do it when when no needed. D2 is about enough in traffic, or at least in the more recent dct software it is. What do you have?

[AshyLarryMP]

I start in D1, power button off, soft edc. Once it's warm I hit the M button to D5, on the freeway.

[SenorFunkyPants]

The first time in the morning when the engine is cold, I do actually pull away in 2nd (in S3). The engine/DCT cold start routine makes the engine rev a little two much for my liking when engaging first so I take second and tickle the throttle to get it moving...then its downhill for while and then its ok and back to first to pull away.

[SSPKris]

Under normal driving conditions the DCT Clutches will not see much wear.

Excessive wear comes from:
Driving the car hard at cold start up before the transmission comes up to temperature
Launching
Adding additional horsepower that exceeds the limits of the stock clutch

We now have a M3 DCT in the shop that we are upgrading the clutch in. The car has 32000 on it, and the clutch plates look really good. There is only .2mm of material that has worn during this time. Now this being said, the car has had a pretty easy life. All clutch wear will vary depending on driving conditions.

SSP

[BzsBimmer]

Great to see you participating in these type of threads Kris!
As our DCT's start aging, it's nice to have a specialist around.

Too bad you're in MN for us West Coast folks. Not many people I'd trust with my DCT other than the dealer, and dealers are $$

[TX]

Originally Posted by BzsBimmer

Great to see you participating in these type of threads Kris!
As our DCT's start aging, it's nice to have a specialist around.

Too bad you're in MN for us West Coast folks. Not many people I'd trust with my DCT other than the dealer, and dealers are $$

Do dealers even open the DCT? I thought that was a swap/ship out item.
I'm curious.

[fleainat]

All great info -- thanks for the help, guys! I just got the car with 45K miles, so I can't vouch for the previous owner, but it seems like it's in good shape.

I plan to keep the car for a long time, so I guess I will try D2 now...

I drive just 5 miles to/from work in West LA gridlock, so it's hard on a car that really wants to be driven!

Passengers get scared when I'm in D4/D5, because it's so loud, especially the convertible.

[SSPKris]

Originally Posted by BzsBimmer

Great to see you participating in these type of threads Kris!
As our DCT's start aging, it's nice to have a specialist around.

Too bad you're in MN for us West Coast folks. Not many people I'd trust with my DCT other than the dealer, and dealers are $$

BMW dealers are not trained to work on the DCT transmission. The only options they have currently:
Replace the transmission
Replace the factory clutch with a new OE unit
Replace factory fluid and filter

This is not going to change as Getrag and Borg Warner keep these transmissions under wraps. The only parts you will see in the near future will be from aftermarket companies.

Currently SSP has performed the following procedures to the DCT:
Aftermarket fluid change with stainless lifetime filter
High performance clutch plates changes (14 and 16 plate)
High performance internal clutch basket seals changes
Total tear down including gear sets and electronics

We currently work on the BMW DCT transmission from all over the world. From race teams in South Korea, to clutch changes in Germany. We have the capability to transport these transmissions and or come to your location to repair this transmission on site.

SSP

[Sandye90m3]

Originally Posted by SSPKris

BMW dealers are not trained to work on the DCT transmission. The only options they have currently:
Replace the transmission
Replace the factory clutch with a new OE unit
Replace factory fluid and filter

This is not going to change as Getrag and Borg Warner keep these transmissions under wraps. The only parts you will see in the near future will be from aftermarket companies.

Currently SSP has performed the following procedures to the DCT:
Aftermarket fluid change with stainless lifetime filter
High performance clutch plates changes (14 and 16 plate)
High performance internal clutch basket seals changes
Total tear down including gear sets and electronics

We currently work on the BMW DCT transmission from all over the world. From race teams in South Korea, to clutch changes in Germany. We have the capability to transport these transmissions and or come to your location to repair this transmission on site.

SSP

Very cool, good to have some knowledgeable of DCT on the board.

Sandeep

[SSPKris]

Our entire business is focused on DCT transmissions. This is all we work on daily.

SSP

[FashionablyFast]

Noticed the OP using D1 and I've always wondered...Is there any gas mileage advantage in using D1? Wear & tear advantage also? ....or no advantages at all other than traction in the snow?

[jakob66]

Originally Posted by SSPKris

Under normal driving conditions the DCT Clutches will not see much wear.

Excessive wear comes from:
Driving the car hard at cold start up before the transmission comes up to temperature
Launching
Adding additional horsepower that exceeds the limits of the stock clutch

We now have a M3 DCT in the shop that we are upgrading the clutch in. The car has 32000 on it, and the clutch plates look really good. There is only .2mm of material that has worn during this time. Now this being said, the car has had a pretty easy life. All clutch wear will vary depending on driving conditions.

SSP

Finally good/qualified info on DCT!
I'm considering 550hp SC kit for my car and are curious if you have seen SC kit equipped DCTs and how the clutch looked like?
When you say "Adding additional horsepower that exceeds the limits of the stock clutch " what does that mean? How much is too much?
I know it's a very subjective question but I don't want to replace clutch every 20k mls as I'm driving 10k/year.
Thanks for info!

[SSPKris]

Originally Posted by jakob66

Finally good/qualified info on DCT!
I'm considering 550hp SC kit for my car and are curious if you have seen SC kit equipped DCTs and how the clutch looked like?
When you say "Adding additional horsepower that exceeds the limits of the stock clutch " what does that mean? How much is too much?
I know it's a very subjective question but I don't want to replace clutch every 20k mls as I'm driving 10k/year.
Thanks for info!

The BMW's DCT transmission is capable of holding quite a bit of torque to the wheels. Its not the horsepower that kills the clutches, its the torque.
Adding a supercharger can almost double the horsepower and out put of the engine. The transmission is not designed to hold this much power. Some modifications will need to be done to keep this transmission reliable at these horsepower levels.

The clutch in the DCT wears the same as a clutch in a manual gearbox. The harder the car is driven, the faster the clutch will wear.

Here are some pictures of a BMW M3 we just changed a clutch in a few days ago. This particular car was running a supercharger and ended up cooking the factory clutch plates after a few weeks.
SMALL CLUTCH 2-4-6


LARGE CLUTCH 1-3-5-7




SSP

[pooyab]

I know that under the M settings you can choose between D and S and the level, but how can you tell if you're on D or S in normal modes?

[crypticc]

Originally Posted by SSPKris

Under normal driving conditions the DCT Clutches will not see much wear.

Excessive wear comes from:
Driving the car hard at cold start up before the transmission comes up to temperature
Launching
Adding additional horsepower that exceeds the limits of the stock clutch

We now have a M3 DCT in the shop that we are upgrading the clutch in. The car has 32000 on it, and the clutch plates look really good. There is only .2mm of material that has worn during this time. Now this being said, the car has had a pretty easy life. All clutch wear will vary depending on driving conditions.

SSP

Oe or afrermarket clutch packs? Can you post before, and after pics of the "good" old clutch packs and assessment of how much life was left in them, I.e. how much after the 0.2mm was left. I'm thinking that if a single disc manual clutch might last 100 thou miles, how long does a multi disc wet clutch with similar driving last. /2 because each clutch is used less. Also has the owner posted a review anywhere? Asking because the grapevine still implies dct clutch pack replacements that aren't OE give issues, and I read that BMW won't sell the OE pack as a separate at all.

P.s. seeing on vag forum to 300 plus isn't uncommon provided they are the wet clutch and not impacted by the cooking issues they had due to lack of cooling and synthetic oil.

[jakob66]

SSPKris quote "... The transmission is not designed to hold this much power. Some modifications will need to be done to keep this transmission reliable at these horsepower level. "


Can you give us some ideas what those modifications would be? The SC kit I'm looking at would be a torque gain of around 135ftlbs. I'm not into drag strips and/or launching the car (my motorcycle still pulls harder )
I will track the car. I'm sure keeping oil temp under control will be one of those options?
Now knowing someone can answer such questions is really great.
This was a major concern and let me put a hold on a SC kit.

[CBS]

^ For what it is worth, I have had my SC (ESS VT-1 550) for several years, put on 24K miles and attended 40+ track days. My M3 is not a DD. I haven't (yet) had problems with my DCT but I do change the Pentosin and filter every winter.

As a side note, I'm very interested in SSP and what they can offer.