If your vehicle is showing rattling noise from underneath the car on rough roads, here are the most likely causes and the parts you'll need to fix each one.
The ball joints at the ends of the sway bar links wear out over time, creating a distinct, rapid clunking or rattling noise when driving over uneven surfaces or small bumps.
Thin metal heat shields around the exhaust often rust at their mounting points. This causes the shield to vibrate and create a tinny, metallic rattle against the exhaust pipe over rough roads.
The rubber isolators in the strut mounts degrade, or the struts themselves lose their dampening ability, leading to a hollow rattle or clunking sound from the wheel wells over rough roads.
If the anti-rattle clips or support springs were left off or improperly installed during a recent brake job, the brake pads will rattle loosely inside the caliper bracket when going over bumps.
Degraded rubber bushings or loose ball joints allow the control arms to shift and knock against the frame when the suspension travels over rough roads.
The rubber hangers that suspend the exhaust system can dry rot and break, allowing the metal exhaust pipes to bounce and rattle against the vehicle's undercarriage.
Plastic underbody panels often lose their retaining clips during oil changes or from road debris, causing the plastic to flap and rattle against the frame.