Maybe your first car was a bit of a rust bucket. It was still cool, right? Nowadays “old” cars are in better shape than they use to be. New materials, manufacturing practices and protective coatings help keep the body looking good, but as they say, “beauty is only skin deep.”
Some Subaru owners may be surprised to find out
their vehicles are being recalled
for corrosion issues. After all, the effected model years range from 2005 right up to 2014. These are not old vehicles. The problem is not readily visible, either. It is occurring with the brake lines; a bad place for things to start rusting through. Understandably, most owners are not regularly checking their condition, and problems can arise with little warning.
The recall only covers vehicles which are or were registered in northern locations which salt their roads heavily. The problem is that this brine solution was getting though a gap in the shielding when it was never supposed to reach the lines. This regional recall method is a topic of contention itself, but remedies are available by either replacing (if condition is bad) or applying a protective wax coating.
Corrosion occurs by the transfer of electrons, and salt accelerates corrosion by increasing the electrolytic concentration and thereby easing the transfer of electrons (and related metal ions). The metal chlorides formed also create a very acidic solution, further accelerating corrosion.
Subaru is not the only automaker dealing with brake line corrosion. GM is under pressure to recall 1.8 million pickups manufactured around the turn of the century because of failing brake lines due to corrosion. GM says it’s simply normal wear and tear, and the responsibility for inspection is the owner’s. While the specific details may be debatable, corrosion is normal.
According the 2002 NACE International report , corrosion costs the US $276B every year. Of that massive number, the automotive sector is only surpassed by drinking water and sewer systems. The endless fight against the second law of thermodynamics is waged in a number of ways.
By far, the concentrated effort to control corrosion is centered on protective coatings. 10-100 times more is spent on coatings over other methods such as using corrosion resistant alloys. It is cheaper to apply a thin coat of passive material than to use a solid material with more favorable characteristics. Practically, this takes the shape of painting and galvanizing instead of using stainless steel or other corrosion resistant materials.
Whether it is up front or over time, corrosion costs. Who picks up the bill, such as with these automotive examples, is another story. Corrosion can range from extreme applications, such as gun barrels , to the seemingly mundane, like brake lines. The universal truth, however, follows the old saying, “An ounce of prevention is worth a pound of cure.”
Image courtesy of
Channel4.com