NefMoto

Dear Gentlemen,

Skoda Superb 2018 2.0t 280 hp with DQ250, current mileage ~90k km. From the day one I owned the car, I'm not convinced that the gearbox operates properly.
Particularly the 5-4-3-2 downshifts in D mode are unsmooth while working brakes are applied. This happens only when brakes are applied. If I let the car freeroll and downshift itself without brakes, all gear transitions are ok. The "unsmoothness" could be described as jolts or bumps accompanied with aggressive engine braking effect.
If I select the Eco mode (with coasting disabled), then everything runs smooth as butter. It's very noticeable that downshifts then happen later, at almost 1k rpm, and without extreme engine braking.

I'm really confused because, as far as I'm aware, D and Eco modes use the same maps...

Any ideas, can it be solved software wise?

Gearbox info:
HW: 02E92777AS
SW: 0D9300018C v. 5201

This statement is completely wrong, Superb gearbox has efficiency mode separate.

i have a late model 2015 passat 3.6 dsg in one car and earlier 3.6 dsg in another and the later one has like a hill decent control when brake pressure and angle of attack are just right so i would say its normal behavior for an mqb dsg if my late model fxx dsg does it. i only recognize it because my 7p touareg has the feature also.

Mileage you have is solid wear out already and many things is already gone - yes you may try prolong its agony with tune - but i suspect budget here equals to 1 can of beer? Right? :)

Can the efficiency mode downshift behaviour be applied to D mode? Tallinn is few hours drive for me.

Please dial down the arrogance. Dealer already did experiments costing me quite some cans of beer.

It is of course possible, but I quit calibration in 2020, so I can not help you.

It can also be that it can be made softer, by lowering the gradient speeds and increasing/decreasing the overlap, as well as playing with the stall speed.
I don't know who has the knowledge and then wants to spend time to do this though. It can take a whole day :D

And because there are certain limitations and quirks with the gearbox (as well as sometimes it's mechanical condition), then it might be difficult to get the end result that makes the customer happy.
So from a commercial standpoint it makes very little sense for anyone to even attempt this job - those who could do it well usually have their hands full with stuff that is much easier and pays much better.

Your best bet is probably get really cosy with the gearbox, get a flash tool, buy a damos and start to study the funktionsrahmen. I doubt you will find anyone who wants to work on this with you, because most people don't know anything except upping the torque limiter and shift rpm.

Weirdest thing is that it tends to rectify itself to bearable level after "drive it like you stole it" session.
My first thought was that it is a mechanical fault, which reacts to gearbox oil temperature, almost ordered new mech unit, but common sense took over me and before that I tested two other random Superbs with same engine + gearbox setup, different mileages and manufacturing years. Both behaved very similar. So the chances that three random cars have same mechanical fault are not so high, same s*** software - way more higher.
Neither two dealerships or two dedicated gearbox service garages could confirm at least somewhat sure mechanical fault due to nature of complaint. Oil was drained, no excessive impurities, mech unit cover was removed - no metallic debris on solenoid magnets.
Only one other thing that might slightly point to an actual mech unit issue is an occasional clumsy 1->2 shift at low throttle. No bang, slap or even jolt, but I can feel it.
Maybe it's worth to do some more experiments with existing mech unit (hydraulic part cleaning + solenoid replacement) during the next scheduled service with a hope that it will at least not make things worse.

After owning three dsg cars I think that my next one will be again with ZF or Aisin conventional automatic gearbox.

As it was already mentioned  - near nobody will help you here as it is custom calibration subject for poor beated hard dct  - it is verry time consuming exercise - and it will cost you more then just a few cans of bear. To simplify - it is not worth time TBH. Again -  as mentioned already - what you can do - is play yourself with CAL - tool to flash, mappack, tool to log and GO!. There plenty folks to answer reasonable questions here to help you out.

Cheers!

The gearbox has a dynamic driver profile from 0-100% and interpolates between two maps (one being 0% other 100%) based on the percentage.

So the formula is map1result*(driverprofile) + map2result*(1.00-driverprofile).
This is for shift RPM.

Anyway, all this stuff you have to do yourself, or just give up on it, this is the real scenario.
If you want to do it yourself as hobby there's easily enough ways to do it quite cheap these days. PCMFlash, the damos is possible to get and also the funktionsrahmen document.
The financial investment is probably below 1000 EUR, it's the time that matters.

Thanks, gentlemen.