Don't worry, our cars won't self-destruct becuase they are made of aluminum!!

anic:
I was making a general comment about aluminum. I'm sure the specific aluminum alloy used in the tub and other parts are chemically optimized to minimize corrosion potential.
Atmospheric corrosion of aluminum is very rare. The metal is very good in these applications, such as cars. It is when moisture or water is introduced that you can get cathodic reactions depending on water, ph, presence of heavy metals, etc.
Probably too much information, but thought I'd pass it on.
Regards,
Wayne