I have a 7 seater trajet and every every now and again I have a dull sounding vibration when going over a bumpy road or hump.
My car has a manual transmission.
Hi - most likely, the vibration you sense is caused by something under the car moving in an excessive fashion. The muffler for example, or other relatively heavy component, may have weak rubber hangers or bushings supporting it, and it is moving - and vibrating - when you go over a pothole or bump. I recommend a vibration inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
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