Since there are two other rattle/noise threads up now, adding this one as I didn’t find anything in a search.

When I reverse out of the driveway, and turn right almost full lock, I hear a loud “dut, dut, dut” noise from the drivers wheel well when braking to a stop. Almost sounds like the tire rubbed the wheel well, but I have TRD wheels, stock size tires and no lift. I don’t see any rub marks.

Sound occurs when 4Runner is still in reverse, it doesn’t happen when reversing left, and has the highest likelihood of happening after it sat overnight.

Ex Toyota tech said it might be the backing plate. Only 31k and never been offroaded, so taking to the dealer next week as I still have warranty coverage.

Any guesses?

I am betting it is barely rubbing on the front mudflap. TRD Pro wheels have lower offset and have known to do that, even stock height/tires

It does sound like it could be the mud flap, but I can’t recreate the noise outside of when I leave in the morning.

A little bit of chalk goes a long way. Rub some where you think it's rubbing. The drive around and try to reproduce the noise. Once you hear it, check to see if any chalk rubbed off. Even tape up some parts and then rub with chalk to get a good bit of chalk on there.