Shocks and Struts: "The Old Bumper Test"
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For years it was not uncommon for shops, dealers and car owners to attempt to test shock and strut condition by jumping up and down on the front or rear bumper and watching to see how long it took the car to stop moving. We even used this method up into the 1980s until we saw a shock test being performed by a Bilstein technician. We were surprised at how fast the shock tester cycled the shock. Have you ever watched a gallon of paint on a paint shaker at the hardware store? He said that it is not uncommon for a car cruising at 60 mph to see the suspension move 1 full inch in 1/1000th of a second. The bumper test might be able to tell you if your shocks are completely blown out, but it won't tell you if they are still working safely. If you are unsure about the condition of your shocks, have an experienced technician at your Volvo dealer or independent repair shop, take your car for a quick test drive. This is the safest way to determine the condition.