Chrysler 300 loud "clunk" when coasting downhill

I have a 2010 Chrysler 300 Signature Series. I have taken it to 3 mechanics re: this issue but no one can find anything wrong. For work I park in a 5 story parking structure. When I’m leaving and driving our of the structure, “downhill” , I coast slowly between the turns and when I lightly put my foot on the accelerator to drive around the corners/turns there is a loud “clunk” and you can feel a little “jerk” in the car. It happens everyday but the mechanics can’t reproduce the sound or the jerk. Any ideas of what this can be? It has happened only twice when on a flat surface, again in the parking lot, when I’m slowly coasting looking for a spot and then give it a little gas to drive forward… the “clunk” and “jerk” Thank you for any suggestions you may have regarding this issue.

Sounds like maybe a U joint, but it’s weird that no one can reproduce it.

On a rear wheel drive vehicle there is often a little slack in the rear end gears and… as the engine is coasting about the same speed as the rear axle is coasting…a tiny chnage is in those speeds can show that slack in the form of bumps.
You’ll notice it does not bump if you accelerate or slow definitively…just during the ‘‘almost’’ equal speed coast.
The slight slack could also be in the transmission or ujoints but is usually just rear end slack.
and…you can MAKE it do it by playing with the rpms while coasting, looking for the no-man’s-land of drive shaft rpm vs rear end rpm.

Is this an AWD vehicle? If so, that might have something to do with it. Sounds tends to get amplified and seem louder than they are in those echoic cement parking structures like that. If it only occurs there, I probably would just monitor the situation to see if it was getting worse over time.

I had a similar problem with an 03 Passat V6. Occasionally the transmission would "clunk’ and the car would jerk, Had it when the car was new and it was still there when I traded it in at 120k miles. I assumed it was a glitch in the transmission.

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