I cannot fathom how a sway bar could rust enough to weaken it. It would have to be eaten away significantly to affect its performance. That seems very unlikely unless attacked by acid or something very corrosive.

I have pulled cars out of fields and never had any damage to sway bars from rust.

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.