Why is the undercarriage made from cardboard!?

[Jmagg73]

I have a 2013 FFH with 58k miles on it, and lately a rattle I've noticed only at high speeds (65mph +) has been getting worse. I look underneath the car and see 2 huge holes in the undercarriage. I guess the wind shoots up into the holes and vibrates the cardboard. I tapped it to see if it was loose and to make sure it was my noise problem. It was, but I notice it was also very flimsy and felt like hard cardboard shipping material.

 

How can this possibly be!? I'm no engineer, but I know what rain, gravel, and salt can do over time.

 

I took two pictures... First was a friends 2014 Fusion SE, and second was my 2013 Hybrid. (Notice the flap of paper-like material still dangling)

 

Soo pissed

 

Would this have a chance of being covered on my extended warranty?

[airbusguy]

I replaced a forward "pan" last year. Car was still under warranty. Pan wasn't. Figured it was rodent damage at the park we were staying at last winter. Not as bad as the guy with the Chevy Duramax 1 ton that had $2500 chewing done to his engine compartment wires. This year he has an electric fence mat underneath. He wants a critter cam for Christmas lol.

[Waldo]

It's not cardboard, it's a fibrous material designed to absorb sound. You could just leave it off it you want to or check junkyards to see if they have a replacement. I wouldn't expect it to be covered under warranty as it's obviously been damaged by some outside input.

[Texasota]

I look underneath the car and see 2 huge holes in the undercarriage. I guess the wind shoots up into the holes and vibrates the cardboard. I tapped it to see if it was loose and to make sure it was my noise problem. It was, but I notice it was also very flimsy and felt like hard cardboard shipping material.

This is probably understood but just to make sure... This is not a structural part of the frame/uni-body. As Waldo said, for sound deadening and it may also play a role in reducing aerodynamic drag at highway speeds.