Rattle sound from underneath the front on Ford Explorer?

Ok,try this

Crawl underneath the car and look next to each of the front tires, there is a metal rod perhaps 18" long.

Inspect and see if that is loose or tight.

Basically as per your description,that metal rod is loose.

See below the diagram,its part number 14:---

Its called sway bar bushings.

Those bushing can be replaced by removing the long bolt that runs thru them, the kit will even come with a new bolt.

If the old nut bolt is too tight,then Hit the old bolt with a little PB blaster spray and let it remain there for 10 minutes.Then try to loosen the nut.

This details will help.

Thanks.

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