Mercedes’s 7G-DCT Transmission (part 1) - Transmission Digest

Mercedes’s 7G-DCT Transmission (part 1)

The reason such a new vehicle came in to Jan’s shop for repairs is the owner had inadvertently bottomed out the car breaking the transmission’s case.

Technically Speaking

  • Author: Wayne Colonna, Technical Editor
  • Subject Matter: 7G-DCT
  • Issue: Broken Case

Several years ago, Jan ten Klooster, an excellent tech in Amsterdam sent me pictures of the 7G-DCT transmission that came out of a 2013 Mercedes CL A 200 1.6L vehicle (Figure 1). This dual clutch transmission came out in 2011 in both the A and B class vehicles. The reason such a new vehicle came in to Jan’s shop for repairs is the owner had inadvertently bottomed out the car breaking the transmission’s case. Figure 2 shows a view of the broken area of the case with the transmission still in the vehicle. Figure 3 shows the transmission out on the bench with the side pan removed. The broken area of the case can be seen below the valve body.

The car owner’s insurance company paid to have a new transmission installed (figures 4 and 5), and Jan’s shop was the one that did the work. Interestingly enough, Mario Aristides (a long time ATSG affiliate that Bob Cherrnay brought on-board) recently brought to us a 7G-DCT for the very same reason. The owner of the vehicle bottomed out the car breaking the case in the exact same way here in the US as it did with the owner of the vehicle in the Netherlands (see figures 6, 7 and 8). This seems to suggest that owners not realizing how easy it is to bottom out their vehicles will be susceptible to this type of damage. So beware, you may find one of these coming into your shop needing the transmission to be exchanged for this very reason.

For next month’s article we will take advantage of having this transmission to look at the inside of it to see how it ticks. It’s very much like Volvo’s DCT450 and Mitsubishi’s DCT470 but with Daimler’s personality built into it.

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