7G DCT Transmission

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The DCT box is terrible in the A45 though, truly awful, never wants to change down when you want it too and unlike the VAG DCT doesn't like to do multiple shifts at once. Much prefer the dim witted MCT box in my C63.

BMW's ZF 8 speed is single clutch and the best auto box I've had a go with.
 
As for the reliability of VAG dsgs as mentioned on the forums, arn't most forums where people and most posts are about problems with their cars. Also autos are generally more complicated in any car.
I had the 6 spd DSG in my Scirocco and it was fantastic, the 7 spd box in my C feels like it takes a nap between gear changes in comparison.

That said, there have been loads of issues with VW's DSG, so much so that I made sure that I desposed of mine before my warranty expired.

In the USA, VW have extended the warranty for DSG boxes to five years, UK is still standard 3 years / 60k.
 
The DCT box is terrible in the A45 though, truly awful, never wants to change down when you want it too and unlike the VAG DCT doesn't like to do multiple shifts at once. Much prefer the dim witted MCT box in my C63.

People have conflicting views of what's good and bad. You can see this when different owners talk about how good a given suspension + wheel option is - or tyres.

I suspect that for those who like to use manual shift the DCT style of box will feel better than an auto with planetry gears.

My assumption is that that the main advantage of the 8HP usining clutch unit over the torque converter isn't efficiency (the 8HP torque converter locks up). It's about those 0-60 times and launch control.

BMW's ZF 8 speed is single clutch and the best auto box I've had a go with.

I no doubt will get corrected but AIUI .....

MB use the ZF 8HP with the clutch pack in place of the torque converter in the E63. It's not really comparable with a DCT. My understanding is that the advantage of the clutch pack over the torqueconverter is launch control.

Just about everybody else (including BMW) use the ZF 8HP with a torque converter. (I would have assumed that the M6 had the clutch version but AFIAA it's also the torque converter version).

In the M5 BMW use a Getrag dual clutch unit. There have been stories that they will eventually offer the ZF 8 speed unit with the clutch.
 
I had the 6 spd DSG in my Scirocco and it was fantastic, the 7 spd box in my C feels like it takes a nap between gear changes in comparison.

But is it actually slower in the real world?

The focus on 0-60 times distorts things. A classic example is the rediscovery every so often that automatics can be quicker in traffic situations than manuals box.
 
I used to have a 52 reg C240 with a nice torque converter auto. It was silky smooth up and down the gears but not especially quick at changing gears - on the up change it would give you a little surge of torque then slack off as it changed up then resume its previous rate of acceleration. Subsequently, I test drove the previous model A-class auto which I think had a cvt arrangement. It was very nice from standstill upwards, and fine on the move, but when coming down to halt, the engine would rumble to very low revs (as if about to stall) then kind of lurch to a stop. This put me right off cvt's and dsg's etc. I have read a review of the VAG dsg which appeared to say a similar thing about it getting caught out at maneuvering speeds.
How does MB's dct in the b-class drive at slow speed??
 
People have conflicting views of what's good and bad. You can see this when different owners talk about how good a given suspension + wheel option is - or tyres.

I suspect that for those who like to use manual shift the DCT style of box will feel better than an auto with planetry gears.

My assumption is that that the main advantage of the 8HP usining clutch unit over the torque converter isn't efficiency (the 8HP torque converter locks up). It's about those 0-60 times and launch control.



I no doubt will get corrected but AIUI .....

MB use the ZF 8HP with the clutch pack in place of the torque converter in the E63. It's not really comparable with a DCT. My understanding is that the advantage of the clutch pack over the torqueconverter is launch control.

Just about everybody else (including BMW) use the ZF 8HP with a torque converter. (I would have assumed that the M6 had the clutch version but AFIAA it's also the torque converter version).

In the M5 BMW use a Getrag dual clutch unit. There have been stories that they will eventually offer the ZF 8 speed unit with the clutch.

I agree that some people probably prefer quick snappy DCT's and some the older type of auto. I have got used to the old type where the revs rise first and the speed follows on afterwards! But I think I could get used to a dct IF the take off and stopping is very smooth. Otherwise I think I would rather use my left foot to control things.
 
I agree that Mercedes need to produce a decent DCT gearbox. The one in my M3 is awesome, lightning fast shifts up or down with throttle blips.

If Mercedes do a decent gearbox in their new C63 I might come back to Mercedes. :)
 

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