Info - Identifying Correct Design Level of Rear Axle Assembly

The purpose of this bulletin is to inform Saturn retailers of a change to service parts availability for Saturn ION rear axle assembly and related components. The current axle assembly supplier has changed, resulting in several component changes. The first design axle assembly is no longer in production. The additional parts that changed to accommodate the second design axle assembly are the jounce bumper, the spring, the spring seat, the control arm bracket support, and the park brake cable.

Saturn ION vehicles built prior to and including VIN breakpoint 5Z150137 have the first design rear axle assembly.

Saturn ION vehicles built after and including VIN breakpoint 5Z150138 have the second design rear axle assembly.

When changing any of these components (jounce bumper, spring, spring seat, control arm bracket support, or park brake cable), you must identify whether the vehicle is equipped with a first or second design axle assembly. This can be done by a visual inspection of the jounce bumper.

The first design axle assembly utilizes the one-piece jounce bumper shown in the illustration above. The end of the bumper (1) will be molded as one piece with the bumper body.

The second design axle assembly utilizes the multi-piece jounce bumper shown in the illustration above. The end of the bumper (1) will be separate from the bumper body (2).

If you are replacing a first design axle assembly, you can use the first design parts as long as they are available. The first design rear suspension bolt/screw, rear suspension jounce bumper, rear lower spring seat, and rear spring are also available for service.

Once first design parts are exhausted, you must order the second design axle assembly kit (P/N 15276261 for FE1 or P/N 15276258 for FE2). You must also order the second design rear suspension jounce bumper, rear lower spring seat, and rear spring. The second design rear suspension control arm support brackets will be used to back service the first design rear suspension control arm support brackets and park brake cable bracket. When you order these kits, you must also order the rear suspension bolt/screw (P/N 11609755) to attach the rear axle assembly to the body. You must also use a second design park brake cable.

There are differences between first and second design torque specifications.

There are differences between first and second design rear alignment specifications for the FE1 and FE2 suspensions.

All the second design level parts are available and can be ordered separately. To service the rear axle assembly, refer to "Rear Axle Replacement" in the Suspension section of the appropriate model year Saturn ION Service Manual or SI (SI Document ID# 871380 for 2003-05 vehicles or SI Document ID# 1619409 for 2006 vehicles).