Don't lose your rear end over rust!

A car that runs and drives great still has an Achilles heel: rust corrosion. For all the preventative maintenance in the world, there's not a lot that can be done once rust has started The frightening thing is, if you don't know it's there, it can be down right dangerous!


Recently I received a phone call from a gentleman stating that he was driving along and her heard a loud noise come from under his car. After that, he said that every time he attempted to accelerate, it felt like the car kept wanting to go sideways. He also stated that he had to drive home very slowly. He called me because he needed to know what was going on. I agreed to inspect


Upon arrival, I found a very nice SUV parked in the driveway. I looked very clean. It was a nice 4 wheel drive, 6 cylinder vehicle. Unfortunately, looking under the vehicle confirmed my suspicions, rust had caused major damage. When the customer first described the concern and told me what type of vehicle he had, I suspected that the problem had to do with the rear end When acceleration is applied on a rear wheel vehicle, the driveshaft is 'twisted' to drive the rear axles, which in turn, rotate the wheels. This is where 'torque' comes into play. To help keep everything in place, either leaf springs or torsion bars are used. If they break loose, the rear end will literally shift back and forth on acceleration. This vehicle has torsion bars, and one was broke loose on the driver side. The break occurred where the arm bolts to a bracket that is welded to the frame (pictured above). The bracket had cracked and broken free due to rust. The customer asked if it could be fixed. Yes, if the metal can be ground and welded. No if there is no good, usable metal. I crawled back under the vehicle and found that rust had hollowed out the frame rail and was beginning to deteriorate the other side of the vehicle also. If the other side broke, the entire rear end could theoretically shoot out from under the car. Not good.


So the bad news for this customer was that rust had permanently disabled his vehicle. The only repair option was to cut out and replace 75% of the frame under the car. This kind of work would cost more than the cost to replace the vehicle. The vehicle was totaled by rust instead of collision. Sadly, the customer had only owned the vehicle for about 3 months and the car lot he bought it from was out of business. Tough day!

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