As I was driving home tonight, I noticed a flapping sort of sound coming from the middle to rear driver side. I have an 08 TL with 51k miles. I searched around and found a few older threads but it seems none of them have identified the cause of the sound. It's most apparent at around 10-15 mph, and goes away around 35 mph. To me it sounds like something is on the tire and hitting the ground as I drive, but I checked the tires as much as the night will allow me and saw nothing.

I'm calling the dealership tomorrow but have any of you experienced this sound and if so, what did you find?

 

How does the car handle at speed?
If the car's handling seems worse-- more jounce, mushy, less firm-- it could be a damaged tire with a separating tread. In daytime, you can visually inspect for a bubble in the sidewalls of the tires.

Otherwise, check for fabric or cardboard caught in the undercarriage of the car.
G/L.

 

I did not notice any difference in handling. I will definitely make sure to check out the tires once more in the morning. Thanks!

 

Did you look under the car? It could be the plastic cover shield with one of the push pins that might have fell off and is flapping around.

 

Figured it out. I checked again this morning and noticed a metal stud or bolt in the middle of my rear tire. I immediately took it to Firestone and they repaired the tire for $30. I'm glad it wasn't a suspension issue!