2000 Mercedes Benz E320. With 118,000 miles, having been well-maintained, and never in a major accident, the front subframe of the car broke all the way through, near the upper control arm. The front end immediately made loud scraping noises. Upon taking it to a dealer, we were told it was not safe to drive. We were first given an estimate of $9500 for the repair, and told it would take five weeks to get a replacement subframe. The mechanic would not express an opinion as to whether it was defective, only that it was very rusty, and that it was broken. We contacted M-B usa. They opened a case, sent out an investigator. M-B usa would not admit that the premature rust, and failure, of that subframe was the result of a factory defect, but they agreed to pay $3000 out of the final price quote of $7500. They made it clear that, if we expected to get more, we would have to sue them. To receive the $3000, we had to sign a release. We then filed an insurance claim with aaa, on the theory that the damage might have been caused by some sort of road incident (pothole, etc). However, the insurance investigator inspected the car (and took photographs), and then denied the claim, noting extensive rust throughout the underbody of the car, and on the front and rear subframe components. My later research discovered, Mercedes-Benz used a type of steel on structural components of their cars called hsla (high strength, low alloy). They used this hsla steel ostensibly because of its greater strength, and crash resistance. In theory, hsla steel should have higher-than-normal corrosion resistance, so it's my belief that Mercedes-Benz either got bad batches of this hsla steel, or they substituted an inferior grade of steel. I don't know how many cars were produced having this problem, but it worries me. People may be driving down the road right now, unaware that important structural components of their cars may be ready to fail.

- Plymouth, MI, USA