Tell me more about DCT

[JimD]

With respect to the selection of either D or S, I believe the current BMW DCT has several in between settings, I seem to remember 6 from a review. The reviewer thought there were, if anything, more than enough. The difference was in how abruptly the gear changes occur and presumably at what rpm.

I haven't driven one yet but would like to. Part of my adversion to normal torque converter autos is the complexity and part is the desire to choose my own shift points. And I am very comfortable with shifting after over 35 years. But there are times I would rather not bother and it seems like it would be possible to get comfortable with manually shifting an automatic after awhile (hopefully it wouldn't take multiple decades). But in terms of simplicity, it seems like DCTs will be more expensive to maintain for awhile until the technology matures some and could be permanently more complex to maintain than a manual, possibly worse than a torque converter auto (which is where I would put them currently).

Jim

[pDz]

Originally Posted by jeremyc74

It can't skip gears, but it will change so fast it won't really matter.

ah.

i found the right thread to continue our discussion.

i hope you're right. the reason why i worry is because VAG DSG downshifting is on the slow side (for my personal taste) in both when it executes my button actuation as well as stepping through the two clutches.

obviously upshifting is much smoother as the next gear is already pre-engaged and this is faster than SMG or double-clutch upshifting (6MT).

[GeeRam]

Originally Posted by Cuz5150

As for the BWM being new, I wouldnt touch it with a 10 ft pole. Something like that, i would wait a year or 2 to be safe.

BMW DCT isn't new though....it's been around for several years already on other models....it's just 'new' to the 135i.

[FJUNO78]

Originally Posted by Cuz5150

As for the BWM being new, I wouldnt touch it with a 10 ft pole. Something like that, i would wait a year or 2 to be safe.

Your logic is flawed. You drive a 2009 135i, which is plauged with HPFP problems the same way a 2008 is, or a 2010 is for that matter.

[SR-71BB]

Hey, I' the new guy! I pick up my 135i w/DCT on the 18th , so i'm very interested in this thread.

I went for the '11 w/DCT over a '10 with A/T so fingers, toes crossed big time! My 1st non MT in years, but sometimes catch heavy traffic and the Wife wants to be able to drive me home.

Also, what is HPFP that you refer to on-going probs with

Thanx,

[emtrey]

may 18th....detailed reports better be posted no later then May 19th or we will kill your HPFP before it kills itself.

[SR-71BB]

Definitely full reports, but I still need to know what HPFP is......

[emtrey]

high pressure fuel pump

[GeeRam]

Originally Posted by emtrey

may 18th....detailed reports better be posted no later then May 19th or we will kill your HPFP before it kills itself.

Hopefully this won't be an issue with the N55















Hopefully.......

[SR-71BB]

Yes, hopefully the N55 will not suffer this! Can't wait for the 18th!

[Crumpet]

hi all, just purchased my 1st 2011 135 convertible and thought id chip in here, as someone who has always had manual sports car I find the dct on my 135i quite good. its great in regards to changing gears both up and down , the only issue i have is the dct seems to have some sort of clutch slip built into the software where as when it kicks down sometimes it sits there for a second and does nothing before it takes off. just loud engine noise with plenty of revs but its like the clutch hasent disengaged. , if they can fix that then the dct gives you the best of both worlds I believe.

cheers
Rob

[Schmoops135i]

Realize this is an old thread but here are my 2 cents. I must also mention that I come from a manual only background. Sure DCT is perhaps marginally quicker then a traditional stick shift, but there is so much more to driving then red light to red light. I don't know about everyone on the board here, I personally might do 10% spirited driving each day compared to 90% of regular driving. How important is that 10%? Very important for me to have a 3rd pedal, as this is where the real driving experience is made for me. 90% of my driving is pretty regular stuff, I would never give up my 3rd pedal for that 10%.

[JimD]

I've driven a M3 with DCT since I first commented on this topic at the performance center during a M school. I like the way it worked but I think the driving experience is all automatic and not like a manual. It definitely will let you hit the rev limiter in M mode, I did it repeatedly (got suggestions (requests) over the radio to stop it). I think I could get used to paddles for track or spirited driving but it would take me more than a 2 day school. The M5 and M6s were the single clutch automatics which definitely shift slower.

Overall I think the difference for the driver between a conventional automatic and a DCT is not great. If the conventional auto is set up with high pressure on the clutches and the right programming it shifts quickly and solidly too. Long term, I can see an efficiency advantage for the DCT and potentially reliability advantage too but I still think it will be awhile before all the software and possibly the hardware side of the DCT is mature enough for these advantages to be consistently realized.

Jim

[WhiteTgr135i]

Here's a neat little video about how DCT works :