[SalamiRenegade]

Hi all,

I am considering buying a GLC Coupe. If I do, it will be my first Mercedes and my first German car.

Browsing Mercedes' website, I noticed that the GLC comes with a 9G-TRONIC transmission whereas the GLA comes with a 7G-DCT transmission.

What's the differnce between the G-TRONIC and the G-DCT? The DCT is a Dual Clutch Transmission? The G-TRONIC uses a Torque Converter instead of a dual clutch?

Which would be smoother, especially during downshifts?

I've always had Japanese cars and currently have a Japanese luxury brand with a 7 speed torque converter transmission. I've always found them pretty smooth on upshifts but often rough and jerky during most downshifts (including my current one). Similar to the jerkiness of a manual transmission being shifted by someone who lacks finesse and doesn't blip the throttle to rev match before re-engaging the clutch.

My father has always had Mercedes and BMWs and currently has a Porsche Cayenne. I've always found them so much smoother shifting than my Japanese cars; near perfect smooth. I've always wondered what's different about their transmissions that makes them so much smoother.

Any information provided is greatly appreciated.

 

[Toobad]

The GLC has a hydrodynamic torque converter, indeed it is the worlds first 9-speed transmission to use one. Because it is a relatively new gearbox they isn't much data about failure rates yet but I think it is safe to say there are very few reports on the internet regarding issues. With 9 ratios available the gear changes are indeed imperceptible. I have noticed just the slightest lag when pulling away from standstill purposefully. It selects 2nd gear by default then short shifts for best fuel consumption although you can select one of the sport modes which tightens things up should you really need those drag strip launches.

9G-Tronic Explained

 

[Grootkoos]

There is a big difference between the two transmissions - not in the smoothness of the upshifts but rather in pulling away. The 7G-DCT transmission is a messy affair when pulling away and you and your passengers will be better off wearing neck braces if you are in a hurry.

My wife drives a B-Class with the 7G-DCT and you really have to concentrate when you pull away from a stop. My GLC, on the other hand, pulls away as smooth as butter.