Aluminum or Galvanized?

[spareparts]

I asked this question at the local trailer shop yesterday. He told me he'll replace a rusted axle on an aluminum trailer, but will not on a tubular galvinized. His point being, the axle is made out of the same stuff the rest of the trailer is made out of, its not worth putting an axle under a trailer that is probably in the same shape as the axle. Glavinized trailers are disposable. However, he did say c channel galvinized to tend to last much longer than tubular