Automotive Smog Check Tips
The Vibrating Ford Van
A Technician was asked to solve a vibration problem on a Ford Van.
During a test drive , the vibration was felt everywhere - the dash ,
steering wkeel , front seat , shoulder belts ; everything was vibrating !
The Tech. balanced all four tires on a Computerized Balancer, even
though wheel weights were put on all four wheels and tires, the vibration
was even worse than before.
The Tech. rebalanced all four wheels, time after time, but the vibration
was still present. The Shop Supervisor then took over the job of solving
the mystery of of "The Vibrating Van". The Supervisor balanced one wheel/
tire assembly and then tested it again after installing weights.
The Balance was still way off !!
The Supervisor broke the tire down and found about 1 Quart of liquid in
the Tire !! Liquid wqs found in all four Tires ! . This is why the tires couldn't
be balanced, every time the Van stopped, the liquid would settle in
The Customer later admitted to using a Tire Stop Liquid in all "4" Tires !
Besides Stop Leak, another common source of liquid in the tires is water
that accumulates in the Storage Tanks of Air Compressors, which often
gets pumped into tires when Air is added. All air compressors storage
tanks should be drained of water reguraly to prevent this from happening.
Automotive Principles Technology - James D. Halderman (1999 Edition)