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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 TopKick C-Series (Conventional) C4/C5 🢒 General Information 🢒 General Information 🢒 Rear Axle Identification

All axle housings have identification tags or identification information stamped on them. There are three manufactures:

Eaton® Rear Axle ID
Object Number: 200579 Size: SF
(1)Axle Specification Number
(2)Casting Number
(3)Rough Number
(4)Capacity
(5)Housing Subassembly Number (Including Tubes)

Rockwell® Rear Axle ID
Object Number: 200581 Size: SF
(1)Rockwell
(2)Normal Axle Load Rating (GAWR)
(3)Gear Type
(4)Carrier Type
(5)Axle Design Variation
(6)Manufacturing Location
(7)Main Differential Nest Type
(8)Hub Type
(9)Axle Specification Number

Differential Carrier

The carrier tag may contain the following information:

    • The axle model
    • The ratio
    • The carrier assembly number
    • The carrier serial number
    • The date of assembly

There are three manufacturers of differential carriers:

Eaton® Differential Carrier ID
Object Number: 200584 Size: SF
(1)Side View
(2)Top View

Dana/Spicer® Rear Axle Differential Carrier ID
Object Number: 200587 Size: SH
(1)Dana® Part Number
(2)Customer Part Number (Optional)
(3)Julian Date Code
(4)Line Set Number (Optional)
(5)Last Six Digits of Vehicle Serial Number (Optional)

Dana/Spicer® Rear Axle ID
Object Number: 200582 Size: SH
(1)Dana® Part Number
(2)Customer Part Number (Optional)
(3)Model
(4)Julian Date Code
(5)Line Set Number (Optional)
(6)Last Six Digits of Vehicle Serial Number (Optional)

Rockwell
Object Number: 200586 Size: SF

Record all of the information on these tags in order to help identify the axle assembly.