M5/6 automatic v. our DCT?

[Ateam]

Just wondering which direction you think M will go in the future as far as continuing to work with a DCT or going to a true automatic such as the M5/6 autobox? They already have torque converter-less automatics that have all the benefits of a true automatic without the bigger energy loss and delay of the Torque converter. I have not driven an m5/m6 but wondering if a 7 speed auto will replace a dct in future M models or you think they will go with dct?

The problem it seems like on a track is inability to skip gears as easily as a single clutch system. Not sure as I do not push the car/tranny to any limit so to me it probably makes no difference but I can see an autobox taking over.

Also curious if anyone knows the shift speed difference between the m5 automatic v. dct or any other performance figures?

[piloto]

The F10 M5 has a DCT, just like the M3, but a bit beefier for the added torque. The X5/X6 M have traditional, torque-converter autos (aka slushboxes).

[piloto]

As for skipping gears, that you need the ability is a myth. Look at any F1 car, or even Moto GP, or any other race car with a sequential manual. You go through the gears, up and down. At no instance on a track would you need to go straight from say 6th to 2nd. Even if you're a trail brake king, your downshifting is done in a straight line. That you can downshift mid corner without upsetting chassis on DCT cars (or 6MT if you're that talented....I'm not) is awesome, but not necessary. So there's no advantage.

The advantage is uninterrupted torque delivery, which dual clutch manuals can do, theoretically, and traditional autos and manual cannot. Although almost all manufacturers put in some bit of timing retardation on the upshift, it's not a complete decoupling of the engine from the trans. That's the main advantage of a DCT. However, there are alternatives. Look at the trans in the new Lambo Aventador. It's a single clutch but has different approach to uninterrupted power delivery.

[Ateam]

Originally Posted by piloto

The F10 M5 has a DCT, just like the M3, but a bit beefier for the added torque. The X5/X6 M have traditional, torque-converter autos (aka slushboxes).

I know this but was asking to compare the two feeling/driving. I commented that there ARE autoboxes without torque converters out there so meant down the line this is an option potentially for M.

[piloto]

Originally Posted by Ateam

Just wondering which direction you think M will go in the future as far as continuing to work with a DCT or going to a true automatic such as the M5/6 autobox?

Fwiw, I interpreted this as you stating that the M5/6 have a traditional auto. But anywho, no, I think BMW will stay with the DCT for now. It's more in-tune with what the M brand personifies, although that keeps changing every day. Now that we're all turbocharged, the trans and diff are one of the major differentiators of the M from AMG, RS, etc.

[swartzentruber]

I'd say the fact that the new M5 is adopting the M3's DCT (even with a turbo) is a sign that M will be keeping the DCT around. Yes, the X5/6M has an auto, but those have higher torque engines because of the extra weight. I know some predict a blending/merger of autos/DCTs, but this is the first non manual shifted trans I've really liked, so there's something about the power delivery of the DCT that could keep them around.

[BeamingE39]

In the near future I believe M division will become like AMG to make greater profits. They already went FI, and over time added immense bulk. Only time before fully-automatic trannys replace DCT

[Ateam]

Originally Posted by NAForever

In the near future I believe M division will become like AMG to make greater profits. They already went FI, and over time added immense bulk. Only time before fully-automatic trannys replace DCT

I agree as it is SO much more cost efficient to use the same autobox across almost ALL bmws, including m and non-m. It will get to the point where it will be an "m-tuned" autobox out of the other bmw's. Just like the m5/6 auto now.

M will simply be taking an engine out of the non-m version and taking their auto tranny and "tuning" them both with boost and some shifting algorithm and call it a day.

SO much more cost effective than using a dct for only 1 or 2 M cars, investing in specific programming, specific tranny, warranty claims to fix a more complicated/rare tranny etc.

I am not necessarily opposed to this as I feel the ZF auto trannies, both 6 and now 8 speed are pretty ridiculously good and shift pretty much as fast as the DCT. It actually shifts more quickly in a downshift situation. Doesn't give you the nice throttle blip though!

[gpitts]

Originally Posted by Ateam

Just wondering which direction you think M will go in the future as far as continuing to work with a DCT or going to a true automatic such as the M5/6 autobox? They already have torque converter-less automatics that have all the benefits of a true automatic without the bigger energy loss and delay of the Torque converter. I have not driven an m5/m6 but wondering if a 7 speed auto will replace a dct in future M models or you think they will go with dct?

The problem it seems like on a track is inability to skip gears as easily as a single clutch system. Not sure as I do not push the car/tranny to any limit so to me it probably makes no difference but I can see an autobox taking over.

Also curious if anyone knows the shift speed difference between the m5 automatic v. dct or any other performance figures?

Good question on direction, and maybe this is a little off topic, but I watched many of the F1 technical innovations stream into the mainstream BMW production cars over the years. Now that they've left F1, where innovation is king, will that negatively impact some of the cool M features we've enjoyed along the way?

[-=Hot|Ice=-]

They've lowered the Drivelogic from 6 bars to 3 bars in the new M5. I'm guessing we'll see that in the upcoming M3 as well. So I'm thinking you have less options on how quickly you want the car to shift in the new M5.

[clar]

Originally Posted by -=Hot|Ice=-

They've lowered the Drivelogic from 6 bars to 3 bars in the new M5. I'm guessing we'll see that in the upcoming M3 as well. So I'm thinking you have less options on how quickly you want the car to shift in the new M5.

I don't read of any reviewer complaining about the reduction to 3 bars. Just how many does one really need anyway? I think 3 is just right cos i doubt anybody ever use D1/D2 or S1/S2 on their DCT now.

[-=Hot|Ice=-]

Originally Posted by clar

I don't read of any reviewer complaining about the reduction to 3 bars. Just how many does one really need anyway? I think 3 is just right cos i doubt anybody ever use D1/D2 or S1/S2 on their DCT now.

You're asking the wrong person. I just wanted to let people know it's been reduced and thus, giving you less options on how fast you want your car to shift.

[BeamingE39]

Originally Posted by clar

I don't read of any reviewer complaining about the reduction to 3 bars. Just how many does one really need anyway? I think 3 is just right cos i doubt anybody ever use D1/D2 or S1/S2 on their DCT now.

I live in Cali so I never needed it, but I've heard that D1 was designed for our snow state residing M3 drivers (starts in 2nd gear). If 3 modes were designed for "normal" conditions and they made a few for dangerous terrain that'd be I know the Evo X has this and my friends driving 450+HP Evos love it.

[mkoesel]

M will go with whatever technology makes the most sense from a performance and cost perspective. For now DCT retains an edge. If, in the future, a planetary box can shift as fast or faster and decrease production costs then they'll switch. It's fine with me as long as we get the best car for our dollar.

[mkoesel]

Originally Posted by -=Hot|Ice=-

You're asking the wrong person. I just wanted to let people know it's been reduced and thus, giving you less options on how fast you want your car to shift.

You're right HI, but this is one case where I agree with the simplification. Five settings is pretty unnecessary in my experience. As long as the settings at the two extremes off max comfort vs. max performance, taking a couple out of the middle is fine. Now, admittedly I rarely use anything but S5.

[captainaudio]

Originally Posted by Ateam

Just wondering which direction you think M will go in the future as far as continuing to work with a DCT or going to a true automatic such as the M5/6 autobox? They already have torque converter-less automatics that have all the benefits of a true automatic without the bigger energy loss and delay of the Torque converter. I have not driven an m5/m6 but wondering if a 7 speed auto will replace a dct in future M models or you think they will go with dct?

The problem it seems like on a track is inability to skip gears as easily as a single clutch system. Not sure as I do not push the car/tranny to any limit so to me it probably makes no difference but I can see an autobox taking over.

Also curious if anyone knows the shift speed difference between the m5 automatic v. dct or any other performance figures?

On the best of breed "traditional" automatics the torque converter is locked up once the car is in motion and does not participate in the gear changing process. Some of these so called "Slushboxes" have gotten very good and give DCTs a good run for the money. Some of the latest designs use a multi-plate clutch instead of a torque converter.

I recently drove a Jaguar XKR-s with a paddle shifted ZF Automatic and an M3 with DCT back to back on a track and on the road. The ZF in the Jag was very good and while the DCT in the M3 was perhaps a bit more hard core the Jag's ZF automatic was an excellent transmission and shifted very quickly and certainly did not make me wish it had a DCT.

[captainaudio]

Originally Posted by piloto

As for skipping gears, that you need the ability is a myth. Look at any F1 car, or even Moto GP, or any other race car with a sequential manual. You go through the gears, up and down. At no instance on a track would you need to go straight from say 6th to 2nd. Even if you're a trail brake king, your downshifting is done in a straight line. That you can downshift mid corner without upsetting chassis on DCT cars (or 6MT if you're that talented....I'm not) is awesome, but not necessary. So there's no advantage.

The advantage is uninterrupted torque delivery, which dual clutch manuals can do, theoretically, and traditional autos and manual cannot. Although almost all manufacturers put in some bit of timing retardation on the upshift, it's not a complete decoupling of the engine from the trans. That's the main advantage of a DCT. However, there are alternatives. Look at the trans in the new Lambo Aventador. It's a single clutch but has different approach to uninterrupted power delivery.

I never got the "skipping gears" argument either as most track cars have some form of a sequential gearbox whether it be with a manual clutch or paddle shifters.
It would be very difficult (and require one hell of a "blip") to downshift from 6th to 2nd mid-corner without upsetting the car.



CA

[wisesoul]

Originally Posted by Ateam

I agree as it is SO much more cost efficient to use the same autobox across almost ALL bmws, including m and non-m. It will get to the point where it will be an "m-tuned" autobox out of the other bmw's. Just like the m5/6 auto now.

M will simply be taking an engine out of the non-m version and taking their auto tranny and "tuning" them both with boost and some shifting algorithm and call it a day.

SO much more cost effective than using a dct for only 1 or 2 M cars, investing in specific programming, specific tranny, warranty claims to fix a more complicated/rare tranny etc.

I am not necessarily opposed to this as I feel the ZF auto trannies, both 6 and now 8 speed are pretty ridiculously good and shift pretty much as fast as the DCT. It actually shifts more quickly in a downshift situation. Doesn't give you the nice throttle blip though!

M5 is a DCT and has never been an Automatic transmission. /thread

[captainaudio]

Originally Posted by Ateam

I agree as it is SO much more cost efficient to use the same autobox across almost ALL bmws, including m and non-m. It will get to the point where it will be an "m-tuned" autobox out of the other bmw's. Just like the m5/6 auto now.

M will simply be taking an engine out of the non-m version and taking their auto tranny and "tuning" them both with boost and some shifting algorithm and call it a day.

SO much more cost effective than using a dct for only 1 or 2 M cars, investing in specific programming, specific tranny, warranty claims to fix a more complicated/rare tranny etc.

I am not necessarily opposed to this as I feel the ZF auto trannies, both 6 and now 8 speed are pretty ridiculously good and shift pretty much as fast as the DCT. It actually shifts more quickly in a downshift situation. Doesn't give you the nice throttle blip though!

The ZF Autos rev match downshifts and will blip the throttle.

CA

[Ateam]

Originally Posted by captainaudio

The ZF Autos rev match downshifts and will blip the throttle.

CA

not the 6 speed zf, atleast not the one I had.

And I meant X5M/6 not m5/6

[valeram]

Originally Posted by captainaudio

On the best of breed "traditional" automatics the torque converter is locked up once the car is in motion and does not participate in the gear changing process. Some of these so called "Slushboxes" have gotten very good and give DCTs a good run for the money. Some of the latest designs use a multi-plate clutch instead of a torque converter.

I recently drove a Jaguar XKR-s with a paddle shifted ZF Automatic and an M3 with DCT back to back on a track and on the road. The ZF in the Jag was very good and while the DCT in the M3 was perhaps a bit more hard core the Jag's ZF automatic was an excellent transmission and shifted very quickly and certainly did not make me wish it had a DCT.

This is the latest trans from the 2012 C63 AMG. From my short drive time of my new C63 AMG (2 months). I still prefer the dynamics of the M3 DCT. The C63 AMG MCT trans, you cannot change the mode from Auto (C,S,S+) to manual while the car is in motion (instructions from the manual). Even though some C63 AMG drivers have been doing it. I just hope that the M3 stays with the DCT.

[captainaudio]

Originally Posted by Ateam

not the 6 speed zf, atleast not the one I had.

And I meant X5M/6 not m5/6

The ZF 6 Speed Steptronic in the 335i will rev match a downshift.

CA