jonpom

When coming to stop, I encounter less lurching if I ease off the brake just as it shifts into 2nd and then reapply light brake pressure right after it reaches 1st. If manually shifting, I lay off the brake while in 2nd until iI shift into 1st gear per above. (I could not do this w/o HUD, else I’d likely crash into car in front of me!)

superswiss

I actually do something similar in my C63. The 3-2 downshift under light to moderate braking and low rpms could be jerky, although I pretty much discovered that it was mostly due to the brakes. I found the original OE brakes to be difficult to modulate smoothly at low speeds, so they would grab too much during the 3-2 downshift and cause the lurch/jerk. This has mostly gone away since I switched to the Brembo full-floating rotors from FCP Euro. They are actually OE rotors, too, found on the C63 Black Series and the GT R w/o CCBs, but they are much easier and more linear to modulate. Still, though, if I want a super smooth stop, I slow down just shortly before it's gonna downshift to 2nd, then let off the brakes and get back on it in 2nd. Then when I'm at a complete stop it shifts to 1st, but at that point thanks to the clutch in the MCT the drivetrain is fully decoupled from the engine. This is actually similar to my technic in manual transmission cars. When coming to a casual stop I usually push in the clutch in third gear and then come to a complete stop, skipping over 2nd gear. Interestingly, the MCT does the same when I drive more spirited and stop harder. It will skip gears for example going 7-5-3 and then 1st at full stop, completely skipping over 2nd. My 2013 Audi RS5 with its dual clutch transmission also seemed to declutch in 3rd already when coming to a casual stop, so similar to my MT technic. It kinda irked me at the beginning that the C63 went 3-2-1 and kept the drivetrain engaged every time I came to a stop, but now that it is 3-2, then declutch and 1st at full stop. It is ok. I would still prefer if it skipped 2nd when stopping casually, just like it does when stopping harder.

BillyTheDude

Risks? I don’t think there are any risks if you switch mode after starting up. If there is one, that would be scaring kids around you when you put it in S+

jonpom

Today I learned that when coming to a stop when I’m in S+ AND Manual shift mode, my GLC43 will remain in 2nd until I come to a complete stop and only then drops by itself into1st. As long as I’m NOT stationary, I can roll along in 2nd at very low mph, as long as I’m remain in manual shift mode.

Ramsino

Yes, that is how the C43 works too. It's strange and causes a very abrupt stop. Also, if you ever coincidentally step on the gas (because the lights turned green the moment you stop) RIGHT when it shifts from 2nd to 1st, the whole car shakes violently lol.

jonpom

Do you manually shift into 1st or wait for car to do it? Since I’ve been employing manual shifting, I rarely get an unwelcome lurch.

Ramsino

If I wait for the car to do it, then it's jerky. So I manually shift into 1st around 5-6mph and that is smoother.

jonpom

Do you get lurch when deliberately in manual mode, i.e., selecting “M” button, not by way of steering wheel paddles? For me, no lurch, no whiplash 😊 when in manual mode.

Ramsino

No lurch for me in manual mode. Sometimes in 1st gear from a complete stop, I do experience the buckling/jerking though.

jonpom

Manual mode seems to be the way to go, ALTHOUGH 1st gear in manual is so quick I hesitate to use manual from launch. When I want to stomp it, I defer to auto and pay attention instead to the sweet exhaust barks between shifts…every bit worth the MSRP! Sweet!!