For use when servicing with a new harmonic balancer on Gen+ V6 & V8 engines that are not equipped with a Crankshaft Position Sensor (CPS). New harmonic balancers p/n 863397 are all machined with a shorter snout to accommodate a reluctor wheel used with a CPS. This spacer fits onto the crankshaft before the installation of a new harmonic balancer to fill the region normally occupied by a reluctor wheel. This prevents disassembly of a non"‘CPS engine to install a reluctor wheel when servicing with a new harmonic balancer.