on a b2500 pickup there is a trim piece that blends in with the drip rail above both doors/ left and right. Sorry, don't know how to explain better. They mount with bolts that you have to remove the head liner to get to. Thanks, best explanation I can think of. they will pop off, I don't know how, they do, mine are gone, Cheap looking, look like $1.00 but probably $100.00 from dealer

 

Do you mean this piece ?

 

IF you are talking the pieces shown in the picture in post #2, then the pricing will be in the $50 Internet to $100 OEM range.

I have never heard of these just blowing away... in fact I was thinking and finding some to replace the ones on my Truck.

I've never removed one of these pieces, what is under it ?

Is it an expansion joint ?

 

They have some on Ebay for '98-2011 models. Molding As for what's underneath - IIRC on the 2002 we had there was nothing but a weld. Not an expansion joint. I have a supercab so my truck doesn't have these.