What's that rattling noise under my car?
A metallic rattle from under the car is most often a loose exhaust heat shield, especially at certain engine speeds. A plastic flapping or scraping noise is usually a loose splash or gravel shield. A rattle over bumps points to suspension parts like end links or worn shocks. Most rattles aren't dangerous, but loose shields can fall off and suspension wear gets worse.
Match the sound to the cause
| Sound | Likely cause |
|---|---|
| Tinny buzz at idle or certain RPM | Loose exhaust heat shield |
| Plastic flapping, scraping on dips | Loose splash shield or gravel shield |
| Rattle over bumps | Sway bar links, worn shocks or struts |
| Clunk from the exhaust when starting or stopping | Broken exhaust hanger or mount |
| Rattle inside the converter when tapped | Broken catalytic converter substrate |
| Sudden loud roar | Exhaust leak or stolen converter |
What we do
We put the car on the lift, tap and move the exhaust and shields, and check the suspension. Sometimes the fix takes minutes, like clipping a gravel shield back into place. Sometimes it's a worn part, and you'll get a photo and a plain explanation either way.
From drivers who came to us
I was panicking bc my car was making sounds!… Dylan saw it was my gravel shield. He popped it back in and sent me on my way, along with a couple pointers.
I went to many auto shops asking for quotes on my Toyota Corolla to fix the rattling noise which was my shocks that needed replacement… the smoothness of my car was very rewarding. Im glad the noise disappeared.
Excerpts from verified customer reviews on Yelp.
More questions
Why does it rattle only at a certain RPM?
That's typical of a heat shield or exhaust part vibrating at its resonant frequency. It often buzzes at idle or around 2,000 to 3,000 RPM.
Is a loose heat shield dangerous?
Not usually, but it protects the floor and nearby parts from exhaust heat. If it falls off, or hangs low and drags, have it secured.
My car suddenly got very loud and rattly. What happened?
A sudden roar from under the car can mean a broken exhaust or a stolen catalytic converter. What to do after a theft.