Retired cop car struts
When replacing the front struts on a 2006-2011 Chevy Impala that’s a former police vehicle (RPO 9C1 or 9C3), you may find one of two different strut designs.The problem occurs when attempting to change the front struts.
To show the old part number, the VIN filter must be turned off in EPC. Either strut may be used on the vehicle, but they must be the same design on both left and right sides. Strut designs cannot be mixed on the vehicle.
Refer to the photos to identify the strut design. If changing from one design to the other, the jounce bumpers must be replaced as well.