GM Service Manual Online
For 1990-2009 cars only

Object Number: 599396  Size: SH

All rear axles are identified by a broadcast code on the right axle tube near the carrier. The rear axle identification and manufacturer's codes must be known before attempting to adjust or to repair axle shafts or the rear axle case assembly. Rear axle ratio, differential type, manufacturer, and build date information is stamped on the right axle tube on the forward side.

    • (1) The first three digits indicate the rear axle ratio.
    • (2) The next digit indicates the axle assembly build source code (D) Detroit (C) Buffalo and (K) Canada.
    • (3) The next three digits indicate the day built, displayed in Julian Date form.
    • (4) The last digit indicates the shift (1) First and (2) Second.

In order to verify reports made on rear axle assemblies, include full code letters and build date numbers.

Refer to Maintenance Schedule in General Information for periodic maintenance and lubrication intervals.