1977-1991 GM Dana 60 Front Axle Identification IDN-119

All 1977-1991 Dana 60 Front Axles in GM 1 ton 4x4 trucks had a Bill of Material Number (BOM) assigned by Dana at the time of manufacture. Th BOM number on 1984-1991 axles is stamped on a Build Tag attached to the differential by two of the differential cover bolts when the vehicle was shipped from the factory but, unfortunately, these tags are often missing on trucks that had prior differential service. 1977-1983 Axles will also usually have the BOM number stamped on the front side of the right axle tube. The BOM number is a 6 digit number beginning with a 6 plus a dash number (ex: 610604-2). They can be used to determine not only the axle model, but also what components the axle was originally built with. We often ask for this number to insure we provide you with the exact parts you need for your truck.

Each different BOM number signifies an engineering part change which may be minor or major and may involve one or more parts. The dash number indicates the axle ratio and, for some years, the front wheel hub style (for single or dual rear wheel models).

Depending on the year and engine GM Dana 60 front axles were available with 3.73, 4.10, or 4.56 gearing.

Cover: 10 Bolt, 12" high

Ring Gear: 9-7/8", 12 Bolt