ImSwirled

2017 C43 110,000km
I get a clunk noise when tapping throttle and letting go, going 40-70km/h. I’m not flooring it at all, just slightly applying throttle and letting off.
Also when i slow down to come to a stop the noise happens. The car shifts and downshifgs perfectly fine when regularly driving.
I’m thinking it could be some type of mount either transmission or maybe diff mount
or maybe a U-joint on the driveshaft? Flex Disk?, CV joint?
I don’t think it is engine mount because i’ve done the brake and gas pedal test and don’t hear a clunking sound.
Any recommendations on what it could be, i’m going to a shop next week so they can dig in deeper to find the issue but i would like to know if someone has something similar or at least a couple of possible causes.

https://drive.google.com/file/d/1PtO...ew?usp=sharing
https://drive.google.com/file/d/1j3a...usp=drive_link
https://drive.google.com/file/d/13fa...ew?usp=sharing

Here are 3 vids, showing off the noise. Any info could be useful. Thanks

W205C43PFL

Although at 110,000 KM it is a little premature for transmission mounts but close enough, it indeed might be that causing your issue.

W205C43PFL

Please keep us posted. The transmission mount is actually super straightforward to replace on our cars. I heard forum members getting it done in 10 minutes. First, inspect the tranny mount for play and the condition visually then decide if you want to replace it or not.

Test everything else for play like driveshaft centre support bushing (mount), check the rear differential for play, check the transfer case for play, the various suspension components such as axles, cv joints, shocks, etc. and bushings' condition, etc. etc.

Best of luck in getting this resolved! Keep us posted : )