Dual clutch transmission charactoristics
12-01-2016, 08:58 PM
#26
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2021 Porsche TTS
interesting discussion. I am confused with Italian's post.
MB refers to it as "Getrag SPEEDSHIFT DCT 7-speed dual clutch transmission"
Can someone explain the differences between the Porsche PDK, VW DSG and AMG DCT?
MB refers to it as "Getrag SPEEDSHIFT DCT 7-speed dual clutch transmission"
Can someone explain the differences between the Porsche PDK, VW DSG and AMG DCT?
12-01-2016, 09:06 PM
#27
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No need for confusion, I was mistaken if it's actually a Getrag trans. I haven't done work on them personally and from what I know I believed they were the same basic design. Sorry for supplying false information.
Last edited by ItalianJoe1; 12-02-2016 at 01:25 AM.
12-01-2016, 11:11 PM
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Trans 722.9 & 700.4 are in no way similar
The MCT trans or 722.931 or NAG2Sport trans is a true automatic trans with planetary and a ravigneaux gearsets. Internal to the trans are 3 clutches and 4 brakes. In place of a a torque converter is the wet clutch which is a multiplate single clutch. In an automatic trans only one gear can be engage at a time.
In contrast the DCT 700.4 trans or Getrag's designation 7DCL750 is a true dual clutch transaxle. This trans is essentially a full manual transmission with two clutches. One clutch handles the odd gears while the other handles the even gears. The reason a DCT shifts so quick is because there are always two gears engaged at the same time however only one clutch at a time.
It should also be noted that the DCT trans in the SLS, and GT(S) is the same (overall). This is also the very same trans found in the 458 and several other Ferrari models.
BTW-trans 724 in the A, B, CLA and GLA is a 7 speed trans not a 9 speed. The function of this trans is identical to the 700.4.
In contrast the DCT 700.4 trans or Getrag's designation 7DCL750 is a true dual clutch transaxle. This trans is essentially a full manual transmission with two clutches. One clutch handles the odd gears while the other handles the even gears. The reason a DCT shifts so quick is because there are always two gears engaged at the same time however only one clutch at a time.
It should also be noted that the DCT trans in the SLS, and GT(S) is the same (overall). This is also the very same trans found in the 458 and several other Ferrari models.
BTW-trans 724 in the A, B, CLA and GLA is a 7 speed trans not a 9 speed. The function of this trans is identical to the 700.4.
Last edited by MBtech1098; 12-01-2016 at 11:14 PM.
12-02-2016, 11:20 AM
#30
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The MCT trans or 722.931 or NAG2Sport trans is a true automatic trans with planetary and a ravigneaux gearsets. Internal to the trans are 3 clutches and 4 brakes. In place of a a torque converter is the wet clutch which is a multiplate single clutch. In an automatic trans only one gear can be engage at a time.
In contrast the DCT 700.4 trans or Getrag's designation 7DCL750 is a true dual clutch transaxle. This trans is essentially a full manual transmission with two clutches. One clutch handles the odd gears while the other handles the even gears. The reason a DCT shifts so quick is because there are always two gears engaged at the same time however only one clutch at a time.
It should also be noted that the DCT trans in the SLS, and GT(S) is the same (overall). This is also the very same trans found in the 458 and several other Ferrari models.
BTW-trans 724 in the A, B, CLA and GLA is a 7 speed trans not a 9 speed. The function of this trans is identical to the 700.4.
In contrast the DCT 700.4 trans or Getrag's designation 7DCL750 is a true dual clutch transaxle. This trans is essentially a full manual transmission with two clutches. One clutch handles the odd gears while the other handles the even gears. The reason a DCT shifts so quick is because there are always two gears engaged at the same time however only one clutch at a time.
It should also be noted that the DCT trans in the SLS, and GT(S) is the same (overall). This is also the very same trans found in the 458 and several other Ferrari models.
BTW-trans 724 in the A, B, CLA and GLA is a 7 speed trans not a 9 speed. The function of this trans is identical to the 700.4.
Thanks for the exact clarity... including the mechanics and numbers.
03-23-2020, 10:44 PM
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03-24-2020, 09:54 AM
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03-24-2020, 02:25 PM
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03-25-2020, 11:16 AM
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‘24 BMW iX M60
You may very well be correct as I was just commenting on how the mode appears to work on my GTR. It would never allow me to travel up to 1/2 mile as you mentioned on flat terrain though; it seems to activate mostly during going downhill, even if only on a slight grade.
