Free 1991 GMC Sierra VIN Decoder

How to decode a 1991 GMC Sierra VIN

Characters 1-3 of a 1991 GMC Sierra VIN

A World Manufacturer Identifier (WMI) is a unique code assigned to every vehicle manufacturer by the Society of Automotive Engineers. It forms the first three characters of the Vehicle Identification Number (VIN), indicating the vehicle’s manufacturer, country of assembly, and type. For the 1991 GMC Sierra, the relevant WMIs are “2GT” and “1GT”, denoting trucks manufactured by General Motors LLC in Warren, Michigan, United States. These codes are pivotal for identifying the vehicle’s origin and type, essential in vehicle registration, recall associations, and historical research. The detailed coverage for these WMIs spans multiple model years, indicating a continuous production line for GMC Sierra trucks under the General Motors umbrella.

List of WMI Codes for a 1991 GMC Sierra

WMI: 2GT

• Model Years Covered: 1989-2009, 2018
• Example VIN: 2GTHC39N4M1507763
• Manufacturer Name: General Motors LLC
• Vehicle Type: Truck
• City: Warren
• State or Province: Michigan
• Country: United States WMI: 1GT
• Model Years Covered: 1989-2024
• Example VIN: 1GTDC14K0MZ501451
• Manufacturer Name: General Motors LLC
• Vehicle Type: Truck
• City: Warren
• State or Province: Michigan
• Country: United States

Characters 4-8 are the Vehicle Descriptor Section (VDS) of a 1991 GMC Sierra VIN

These characters correspond to components like:

• Engine type
• Transmission
• Model or trim
• Body style
• Gross vehicle weight range

Below find the known vehicle descriptor codes for a 1991 GMC Sierra:

Auto manufacturers have some discretion to decide how they want to code this section, but its contents and decoded results are generally consistent.

Character 9 is the “check digit” in a 1991 GMC Sierra VIN.

Based on a formula developed by the US Department of Transportation, it helps reduce fraud by ensuring the validity of the VIN.

10th Character in the 1991 GMC Sierra VIN — Year Code

11th Character in the 1991 GMC Sierra VIN — Plant Code(s)

Known 1991 GMC Sierra Assembly Factory VIN Code(s)

VIN Characters 12 - 17 of a 1991 GMC Sierra

The final 6 characters in a 1991 GMC Sierra’s 17-digit VIN are its serial number, which will be unique to every vehicle.

What info can a 1991 GMC Sierra VIN reveal?

• Model Year: The VIN can reveal the vehicles model year being the year 1991, providing insights into the age and potential market value of the vehicle.
• Body Class and Type: A VIN can specify the body class, possibly indicating a Pickup with a 2-door configuration for the 1991 Sierra, offering detailed insights into the vehicle’s design and structure.
• Engine Details: Important engine information, such as it possibly being a V-Shaped, 5.7 L (347.835 CI) with 8 cylinders and designed by CPC, may be determined from the VIN.
• Fuel Specifications: The primary fuel type, in this instance being Gasoline, along with the possible fuel injection type being Throttle Body Fuel Injection (TBI), can be outlined by decoding the VIN.
• Drive Type and Weight Class: The VIN can possibly specify the vehicle’s drive type, possibly indicating 4x2, and gross vehicle weight rating, possibly indicating this truck falls into Class 2H.
• Manufacturing Information: Location specifics, such as the vehicle possibly being assembled in Pontiac, Michigan, United States, may be extracted from the VIN.
• Additional Features and Capabilities: The VIN may possibly provide insights into special capabilities or options, such as the engine’s possibly being compatible with LPG conversion.

Sample VIN Decode Report for a 1991 GMC Sierra