[gmarch]

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Stock 2020 M2C with about 12k miles...

I have noticed from early on that when I go over uneven roads (like man hole covers or road patches) and I'm heavy on the throttle, I will hear/feel a loud bang from what I think is the passenger rear when the rear tire goes over the spot.

Normal driving, normal power, no issues.

I don't see anything under the car (haven't had it up on a lift though).

Has anyone else experienced this? Any ideas?

[stefan]

Sounds like a bit of wheel hop. NBD.

Though I will say the diffs on these cars are a bit odd. I've had two M2s with two diff failures. Though a bang won't be it. That sounds more just like an inevitablility of stiff chassis over an uneven surface while the diff is in some state of lock.

[gmarch]

Originally Posted by stefan

Sounds like a bit of wheel hop. NBD.

Though I will say the diffs on these cars are a bit odd. I've had two M2s with two diff failures. Though a bang won't be it. That sounds more just like an inevitablility of stiff chassis over an uneven surface while the diff is in some state of lock.

That's what I was thinking, but it's loud and figured I'd see what other people have experienced. I've had some pretty stiff cars in the past and they never made that kind of noise.

[stefan]

Originally Posted by gmarch

That's what I was thinking, but it's loud and figured I'd see what other people have experienced. I've had some pretty stiff cars in the past and they never made that kind of noise.

Could chalk it up to near zero sound deadening and very stiff diff mounts.

[COChris]

Originally Posted by gmarch

Stock 2020 M2C with about 12k miles...

I have noticed from early on that when I go over uneven roads (like man hole covers or road patches) and I'm heavy on the throttle, I will hear/feel a loud bang from what I think is the passenger rear when the rear tire goes over the spot.

Normal driving, normal power, no issues.

I don't see anything under the car (haven't had it up on a lift though).

Has anyone else experienced this? Any ideas?

I recommend lifting throttle when going over patches or man hole covers. This is why road cars have rubber bushings throughout the suspension linkages.

[GerryM5]

Wheel hop. Pick your acceleration roads more carefully. Depending on surfaces all very high performance cars will have this problem.

[terrywang]

I've been having similar issues on/off for the last few years. I noticed it happens when driving on uneven rough road surface (Sydney Northern Suburbs' have undulating gradients), the noise sounds like aluminium cans being crushed and squeezed, metal friction noise.

As some already pointed out, the F87 M2 chassis comes from the F82 M4, hard linkage between the rear subframe and body, no rubber bushings.

What I normally do is to ease on throttle and be very slow and careful over those poor roads. Recently I happened more easily as the extreme weather (so so so wet due to La Niña) caused many deep potholes on road in many residential suburbs, sigh...

NOTE: I even got shocked many times when riding my Giant Roam 3 - it has front suspension but hard tail around where I live, the impact passed onto rider is phenomenal, damn potholes & arch -_-z