Centramatic "ON-BOARD" Balancers permanently mount to the vehicle, (between the wheel and hub on the front and between the wheels on the dual rear). The product uses centrifugal force and deflection from rotation to automatically distribute free moving weights (durametal and synthetic dampening fluid) sealed in the balancer. These free moving weights or balancing media, precisely balance the entire assembly. This includes the tire, wheel, hub, drum/rotor even rocks in the tread or mud, snow and ice stuck to the wheels. Critical to balancers of this type is the amount of balancing media used. Simply stated if 8 oz. if imbalance exists, 8oz. or more of balancing media must be available to counter its effect. The remainder will space out evenly in the tube. This is why Centramatic balancers depending on size, have from 16-32 oz. of balancing media, available if needed.

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Frequently Asked Questions
Technical Information
Video Demonstration

FYI...these are EXCELLENT for prolonging the life of All Terrain and Mud Terrain tires used regularly on the street! They also do a GREAT job of eliminating those small nagging vibrations that happen only at certain speeds...the ones that computer tire balancing never seem to cure.