I don't know the chemical properties of the bumpers but they seem to be sort of a cross between aluminum and steel. They don't rust and they are a lot stronger than plain aluminum. They are some sort of an alloy, I think. The old volvo bumpers are about the same stuff.

If you have ever tried drilling a hole in them you will know they are not ordinary aluminum.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.