Transfer Case Identification

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Transfer Case Identification Tag

Courtesy of GENERAL MOTORS CORP.

An identification tag is attached to the rear half of the transfer case. The tag provides the following information:

Model number (1)
1. First Digit-1 =Single Speed, 2=Two Speed
2. Second Digit-3 =T-Truck, L-Van, 4 or 6 = GMT 800
3. Third Digit-1 = Manual, 3 = Electric Shift, 6 = Automatic, 9 = All Wheel Drive
Assembly number (2)
Serial number (Date & Shift Code) (3)
Low range reduction ratio (4)

The information on this tag is necessary for servicing the transfer case. If the tag is removed or becomes dislodged during service operations, keep the identification tag with the unit.