Unit Bodies Need Special Work
Question: My 1987 Chevrolet Cavalier station wagon was rear-ended, resulting in major damage. They tell me my car is worth $6,000 and the repairs will cost about $3,500. The top appears out of shape. My question is whether they can repair this kind of damage, will it look satisfactory and will it be safe?--R.J.
Answer: A good body shop can fully restore the function, appearance and safety of the car, but a chop shop will butcher your car and endanger your life.
Your Cavalier has what is called unit body construction, which means instead of a traditional beam type of frame, it depends on body panels and sheet metal to provide structural strength to the car.
If you have been rear-ended and the roof has deformed, then your car has major structural damage, and almost certainly the bottom of the car is similarly deformed. The deformation most likely has resulted in the car no long being level--something referred to by body experts as the car’s datum.
Unibody cars are designed to absorb the shock of a collision before it is transferred to occupants. Thus, as the point of collision collapses, surrounding body panels will be drawn into the collision in unpredictable ways. Doors may bow outward. Fenders may be sucked in. In your case, the roof was bent. Some damage can be hidden and difficult to find, according to Ken Zion, owner of Automotive Collision Consultants.
Thus, the problem is finding a body shop that is capable of performing complex unit body restoration, which requires substantial training and specialized equipment.
One way to check the qualifications of employees in a body shop is to see if any of them hold certifications from the Inter-Industry Conference on Automotive Collision Repair. The organization sponsors classes in such technical areas as collision diagnosis, frame straightening, measuring and welding.
It is important to remember that body shops have high turnover of employees. Many body shops do not directly employ the people who will work on your car. Rather, they are contractors who are paid a commission fee based on the amount of the repair.
Proper equipment is also critical.
A qualified shop must have a multiple clamping frame straightening device, which can hold the car precisely straight while the bent portions are pulled. These racks cost $20,000 to $60,000.
To correctly straighten a car, a body shop technician must be able to precisely measure a car. So another important piece of equipment is a multiple measuring device, capable of giving the measurements from any point on the car to a series of other points. Some shops even use laser devices. A chop shop will use a measuring tape, which does not work well.
Finally, you should look over the general cleanliness and organization of a body shop. If the shop is messy and disorganized, chances are that is the kind of repair you are going to get.
If your estimated cost of repair and value for the car are correct, it makes sense to have the repair performed. The rule of thumb in the collision industry is to perform repairs costing up to 80% of the value of the car.
Vartabedian cannot answer mail personally but will attempt to respond in this column to automotive questions of general interest. Do not telephone. Write to Your Wheels, Times Mirror Square, Los Angeles 90053.