farmerjones

I have to disagree!

I'm completely referring to the internals of these transmissions. Audi doesn't need to completely redesign the transmission to handle more power, it simply needs some internal upgrades....some uprated bearings or clutch packs is likely all that is really needed, especially if you want to handle a mere 15 ft/lbs more torque (like a TT RS) for the S4. These components already exist in the DQ### transmission. The testing has all been done, and there is no big engineering projected needed to upgrade this transmission. Heck, it's likely some DQ parts and interchangeable with the DL.

I never said the transmissions are the same or interchangeable....I'm saying the experience and expertise of design have been done and could easily be applied to this transmission. VAG is one of the best at sharing components across multiple lines of cars. They simply didn't do what customers wanted and now have a clumsy transmission tune that doesn't match the performance image the S/RS cars are supposed to have.

ArvX147

Spoken like someone who has no idea why the DL501 was problematic. It is a huge engineering problem because currently the electronics of the DL501 are entirely susceptible to the heat generated by the trans. The design is flawed at the very core of its implementation, I don't claim to know how they would fix it.

Also, no, none of the parts are shared between DQ250 and DL501

DQ250

DL 501

farmerjones

There is no need to be condescending. I am very knowledgeable about the technical side of these transmissions and have a background in the auto industry, particularly the design/repair of drivetrain systems.

If you don't think there are shared parts then you are wrong.....see all those gears, clutched, bearings, solenoids? Grab a parts book and start cross-referencing - you will find identical part numbers. But that's nearly besides the point..... If you don't think creating some upgraded clutch packs and bearings would be a simple task to allow the DSG to be put in the S and RS models then I don't you have a firm grasp on the point I am trying to make. The technical understand and engineering of upgraded components already exists in other transmissions and is ready to be adapted. They could have chosen the Porsche 7 speed design and implemented in here without issue. We are simply talking about upgrading internals, so it makes no difference the shape or application of the transmission.

Lisent, I'm not here to quarrel or belabor my point. We can agree to disagree. I'm simply expressing my opinion as someone that is not an "arm chair quarterback" but as someone with first-hand insight and understanding to transmission selection and design in the auto industry. That's all. You can choose to agree or believe my viewpoint or not.

ArvX147

upgraded clutch packs doesnt fix too much heat in the system. The mk7 Golf R and S3 had to be fitted with two auxiliary radiators to cool the trans at an acceptable level for the torque.

The problem with the DL501, and I guess I will say it for a 3rd time, is that the mechatronics are susceptible to clutch pack heat which is dependent on power coming through the trans and the amount of allowed slipping (which is a function of transmission "smoothness"). The whole longitudinal DSG package needed to be redesigned, so they left it off this series of cars.

I'm quite certain that the supply chain demands of putting a porsche dual clutch in every B9 platform S car exceed the capacity for production and certainly wouldn't line up with their cost model.

machz

Another problem is the weight of the s4/s5 compared to the s3 or the TT. The additional weight also will generate heat and stress on the transmission.

Honestly the car is a but of a dog in normal drive as I would expect it to be but in "S" I don't see the lag people are talking about.

NoMoreBMWs

I think the writing is on the wall for DSG/DCT in high torque applications built to a budget. That suits me fine - the DCT in my 2010 E92 M3 failed, and it was going to cost $17,000 to replace it.

S5xyBack

Definitely sluggish when in D, but an absolute rocket in Sport /Manual. I don't mind, I just drive in D when there's traffic and a quick pull of the shifter transforms the car immediately when the roads clear up. Also, I'm actually getting the claimed 21mpg in city driving. I just pretend I'm driving a A5 when in D, and a S5 in S.

Kris Hansen

Simple fix - run it in manual mode. I would never expect any "automatic" to have instant response *especially* if you ask it to downshift.

Glisse

The highest volume Porsche PDK transmission is the DL501, as used in the Macan. The DL501 is also still used in the current S6. The PDK used in the Panamera, which is a very similar design to the DL501, is made by ZF and not within the group.

You are using marketing walls between Volkswagen, Audi and Porsche, which don't apply to the way they form engineering teams within the Group - which also includes their suppliers, such as ZF. And most of the in-house transmission parts (for 7 of the VAG brands) are made at the Kassell facility in Germany, which is run by Volkswagen. The DQ transverse series dual sequential gearboxes were originally a Borg-Warner design, and I am sure many patents are still active. But it has been through much internal development, and iterations. So many, that to make a sweeping generalisation of DQ gearboxes vs DL series is just wrong.

Funnily enough, overheating due to clutch packs temperatures was an issue with the DQ series when the dry clutch 7 speed was developed (against the 6 speed wet clutch). As a result, Audi designed a wet clutch system for the 7 speed DQ. But then there were overheating problems with both the 6 and 7 speed wet clutch versions due to overheating in hot climates. This was solved by Volkswagen developing a different oil specification.

The DL501 uses two separate oil systems, one ATF and the other gear oil. At introduction of the DL501 (2008), the existing DQ transmissions only had a single oil system, which created compromises between the lubricating needs of the clutch packs vs the gears and shafts. The Mechatronics system (there are 3 core components) and the clutches share the ATF system in the DL501. One of the Mechatronic system components is the electronic gearbox control unit, and this is sensitive to heat, as all electronics are. The ECU within the Mechatronics system has an internal temperature sensor, and the trigger point is 135°C. Above this, the engine will start to cut torque (power is irrelevant). There is also a sensor for the ATF fluid, and the trigger point is 160°C. Above that, and the clutch packs will be damaged. Again, the system cuts torque. The ATF is cooled by a dedicated radiator section. But if people get an after-market tune from laptop engineers, which usually boost mid-range torque because that's easy on a FI engine, the torque reduction from temperature sensors being triggered may not be sufficient to lower temperatures.

I've had two models with the DL501 for a combined ownership period of 13 years. Of course there have been Mechatronic failures, but over the life of the B8 S4/S5 forum just here, how many owners had a failure? And the skill set required to repair these is beyond most official dealers' "technicians". Or the labour costs would be astronomical. As a result, any problem usually results in changing the entire Mechatronics system. Whether the failure was with the hydraulic actuators or the electronics, and it was specifically related to a sensor failure resulting in overheating is rarely mentioned.

Claiming, either 1 or 3 times, "It is a huge engineering problem because currently the electronics of the DL501 are entirely susceptible to the heat generated by the trans. The design is flawed at the very core of its implementation, I don't claim to know how they would fix it." is ridiculous. In the broader family of VAG dual sequential transmissions, it is the dry clutch 7 speed MQ/DSG that was flawed in engineering terms.

The new Audi C8 A7, which goes into production next week, is using an S tronic transmission with the "55" (EA838 family) KoVoMo engine, with slightly less power and torque than the version used in S4/S5. And is also using a quattro Ultra system.

Go figure.

prashanth1337

I have to confess, I am a complete newbie still learning about cars and their mechanics. Nothing made sense to me from Glisse's post. But damn! Glisse killed it. I love this forum.