"We have a Skoda with DSG.

The manual explicitly says do not hold the car on the accelerator. The reason is obvious when you know how it works."

HOW MANY owners of a new car read the manual?

and How many users of a second hand car have a manual , let alone readit.

Indeed. Most people read (or when they do, understand / fully comprehend [often as it's either a translated document or one complied by someone where English isn't their first, or maybe even second language]) the manual for their TV or HiFi, let alone car. At most, people will check to what the tyre size/pressure whould be (if not on the door plate) and what engine oil type is needed.

Typical VGA: poorly designed.. rather like Ford's Powershift

I'd say that Ford's was worse. The main reason why VAG's gets cited more often is that there are so many more of them around due to the many sub brands and them staring production a lot earlier than Ford did.

I drive a Honda Jazz CVT : no issues in 10 years of wonership. The only dos and don'ts are don't move into Reverse when moving forwards..

That last 'don't' is covered in my 16yo Mazda3's manual for both the manual and TC auto gearbox versions - never a good idea for any gearbox to go against the direction of current travel.

The only CVT issues I've heard of were in Nissans, and normally at a much later stage in the component's life than in DCTs for similar usage. IMHO more likely due to the lesser engineering quality of Jatco boxes compared to, say, Aisin.

>>Typical VGA: poorly designed.. rather like Ford's Powershift

I assume you mean the gearbox, not the manual?

I wouldn't say badly designed. Inappropriate for the application, maybe. In a sense they are an engineering triumph.

My recollection is that DCT were developed by (or for) Porsche for racing. The standout feature is millisecond gear changes. Within reason, durability is less of an issue on a GT racing car than on a consumer vehicle as is refinement. Gear changes would normally be commanded by steering wheel switches but given that actuation is electronically controlled, it is feasible also to have automatic control

Bragging rights aside, the virtually instant changes don't matter for a family hatchback. But the absence of a power-sapping fluid drive means a leap in economy. Irrelevant for racing but a major consideration on consumer cars.

Unfortunately ordinary private motorists spend much more time manoeuvring, starting off, and crawling in traffic than GT racers. And if the DCT is sold as "automatic" then those habituated to autos will (1) expect them to behave like the ones they have driven previously, (2) drive them in the same way, and (3) not bother too much with reading the manual.

The manufacturers have continually improved the programming to make them behave like proper autos. The wet clutch DSG's are very close now, the dry clutch ones less so but still passable. The programming is very sophisticated IMO.

Nevertheless they have proved, if not inherently fragile, then perhaps susceptible to failure consequent on the manner of use. Actual information in the public domain seems spa*** - naturally the manufacturers aren't very up front about it. The fact that some are reverting to epicyclic/TC type autos is telling.

It doesn't help that the dealers just pass them off as "automatics". To me they will always be a fudge, pretending to be something they aren't.

When DSG gearboxes came in nearly 20 years ago a typical auto was 4 or 5 speed and the hit on economy and emissions on particularly diesels was significant when attached to one. A 10mpg difference was not untypical.

Manufactures tried various solutions including CVT (e.g. Audi) and automated manuals (e.g. PSA). DSG/CVT was by far the nicest to drive.

With the advent of 8 speed autos the difference is small or negligible.

I suspect there will be little more development of either autos or DSG/DCT. There won't be the time to get development costs back before they are all defunct.

Edited by pd on 25/11/2022 at 16:28

Yes very interesting. What is the advantage of these fancy gearboxes? Lower cost of production, emissions?

Fuel economy and emissions are lower with DCTs than conventional torque converter automatics

Indeed - even where makes have improved the efficiency of troque converter auto boxes, they still lag about 10-15% behind in efficiency compared to a CVT, DCT or (when used properly) manual box.