center roof support

[anlauto]

Oil canning?

A moderate deformation or buckling of sheet material particularly common with flat sheet metal surfaces Typically caused by uneven stresses at the fastening points This terminology also refers to the popping sound made when pressure is applied to the deformed sheet forcing the deformation in the opposite direction. 

[Bullitt-]

Oil canning?

metal that pops in with slight pressure and back when pressure removed reminiscent of the old oil cans you pressed on the bottom

[JS29]

  Sometimes caused by metal stretch. 

[dodj]

Oil canning?

metal that pops in with slight pressure and back when pressure removed reminiscent of the old oil cans you pressed on the bottom

Ah, ok, that makes sense. Alan, your description was too cerebral for me.

[anlauto]

Ah, ok, that makes sense. Alan, your description was too cerebral for me.

I meant it as a joke.....I just Googled it and that was the definition that came up.... I think the picture was much easier to understand as well