Hi all. Has anyone ever looked between the front of the box and the back of the cab just below the rear window? There are two "things" on the cab wall. Anyway,I've been searching for a rattle on my '99 F250 SD reg. cab that seemed to come from just behind the drivers seat when the frame flexed. These things are close to the box and look like they might be my noise. Any ideas? Thanks, Skydan

 

I believe they are plastic air vents. I think they are there so that the air coming in your dash has a place to go "out" when your windows are rolled up, that way the air keeps circulating.

 

>I believe they are plastic air vents. I think they are
>there so that the air coming in your dash has a place to go
>"out" when your windows are rolled up, that way the air
>keeps circulating.


Yup, they are made with a "flap" or "check flap" so air can escape but not enter.

 

Also necessary to keep glass from flying when you shut the door(s) with the window(s) up.

I wouldn't think the vents could move enough- or with enough force- to make noise. Have you checked the cab mounts?

 

I found the rattle behind the drivers seat. It was a loose clamp on on the toneau cover mounting rail. Thanks for the input. Now if I could just find that noise over there....... See ya later, Skydan