Mack VIN decoder,
from the NHTSA record.

A World Manufacturer Identifier is the first three characters of the VIN. NHTSA assigns each one to a manufacturer, and vPIC records the vehicle type and country it was issued for. The 3 codes below are the ones verified for Mack in vPIC: 1M1, 1M2 and 1M3. The list is built from the manufacturers the VINs sampled for this page decode to, and NHTSA can have issued Mack other codes for other plants and vehicle types. 2 of them appeared in the 150 Mack VINs sampled from FMCSA roadside inspection records for this page; the rest are registered with NHTSA but did not show up in that sample.

1M2MDBAA4RS011167 is a Mack truck recorded in a roadside inspection and decoded clean by vPIC. Reading it left to right:

• Positions 1 to 3, 1M2. The WMI. vPIC resolves it to MACK TRUCKS INC., filed for incomplete vehicles and assigned to United States.
• Positions 4 to 8, MDBAA. The vehicle descriptor, whose meaning Mack's manufacturer defines in its filing. For this VIN vPIC read model MD, body class Truck, GVWR Class 6: 19,501 - 26,000 lb (8,845 - 11,794 kg) and engine B6.7 from these five characters.
• Position 9, 4. The check digit, computed from the other sixteen characters. vPIC reports this VIN with error code 0, so the digit calculates correctly and the VIN was read right.
• Position 10, R. The model year code. vPIC decodes it as 2024. vPIC flags the code as ambiguous for this filing (year codes repeat every 30 years), so confirm against the certification label.
• Position 11, S. The assembly plant. vPIC names Salem, Virginia, United States.
• Positions 12 to 17, 011167. The production serial. It identifies the unit and decodes to nothing on its own.

vPIC's own pattern for this unit is 1M2MDBAA*RS: the positions it decoded from, with the check digit masked. Two Mack VINs that share that pattern share every attribute vPIC filed for it and differ only in the check digit and the serial.

Two reads of the gross vehicle weight rating, both from the federal record. First, what the manufacturer registered with NHTSA:

• MACK TRUCKS INC. Registered with NHTSA in Greensboro, North Carolina, United States as Completed Vehicle Manufacturer and Incomplete Vehicle Manufacturer. Registered vehicle types: Truck, Class 6: 19,501 - 26,000 lb (8,845 - 11,794 kg) to Class 8: 33,001 lb and above (14,969 kg and above) (primary); Incomplete Vehicle, Class 6: 19,501 - 26,000 lb (8,845 - 11,794 kg) to Class 8: 33,001 lb and above (14,969 kg and above). 150 of the sampled Mack VINs decoded to it.

Second, the GVWR class vPIC returned for each of the 150 Mack VINs in the sample:

• Truck-Tractor: 78 units
• Truck: 72 units

If the VIN is not to hand, the rating is on the certification label on the unit itself; how to find GVWR walks through where to look.

3 real Mack VINs from FMCSA's roadside inspection file, each decoded by vPIC with error code 0. Every field shown is what the manufacturer filed; a field that is missing was not filed for that pattern. Paste any of them into the decoder above to see the full card.

FMCSA's Inspections Per Unit file (data.transportation.gov, dataset wt8s-2hbx) records every vehicle in a roadside inspection with the make code the inspector typed. It holds 151,931 truck tractor records under the code MACK and 140,027 straight truck records under the code MACK. Native Base pulled 150 distinct VINs from those codes and sent them to NHTSA vPIC in batches: 150 came back, 150 decoded as MACK, and 150 with a clean error code. The decode, not the inspector's code, decides what a unit is, which is why the same make appears under several spellings in the file.

• Model years in the sample: 1984 to 2024.
• Plants vPIC named most: Macungie, Pennsylvania, United States (132), Salem, Virginia, United States (7) and New River Valley Dublin, Virginia, United States (5).
• Vehicle types vPIC lists under the MACK make: Truck, Bus and Incomplete Vehicle.
• WMIs verified one by one through vPIC DecodeWMI; manufacturer registrations from GetManufacturerDetails. Fetched 2026-09-27.

The same record, page by page. The truck and trailer VIN decoder takes any VIN and explains what a decode returns; each page below carries one manufacturer's WMI codes, VIN pattern, GVWR classes and worked decodes.

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• Decode International VINs: WMI 3HS and 3HA, GVWR classes and worked examplesInternational VIN decoder →
• Decode Western Star VINs: WMI 5KJ and 5KK, GVWR classes and worked examplesWestern Star VIN decoder →
• Decode Hino VINs: WMI 5PV and JHH, GVWR classes and worked examplesHino VIN decoder →
• Decode Isuzu VINs: WMI JAL and 54D, GVWR classes and worked examplesIsuzu VIN decoder →
• Decode Utility trailer VINs: WMI 1UY and 3UT, GVWR classes and worked examplesUtility VIN decoder →
• Decode Wabash trailer VINs: WMI 1JJ, GVWR classes and worked examplesWabash VIN decoder →
• Decode Great Dane trailer VINs: WMI 1GR, GVWR classes and worked examplesGreat Dane VIN decoder →
• Decode Hyundai Translead trailer VINs: WMI 3H3, GVWR classes and worked examplesHyundai Translead VIN decoder →
• Decode Stoughton trailer VINs: WMI 1DW, GVWR classes and worked examplesStoughton VIN decoder →
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Checking the same unit against the FMCSA crash file? The VIN crash check takes the same 17 characters.