The harmonic balancer under your hood dampens the vibration from heavy torque, while also serving as a pulley for drive belts. It's a key component to avoid a cracks in the crankshaft and other engine failures. When shopping for a replacement, Pioneer offers an extensive line of balancers for domestic and import cars, trucks, and vans. These parts are a tremendous value, especially when compared with the damage possible via a faulty harmonic balancer.