Every vehicle sold in North America since 1981 carries a unique 17-character Vehicle Identification Number (VIN). It is not random — each position encodes something specific about the vehicle. Here is how to read an FCA (RAM, Dodge, Jeep, Chrysler) VIN position by position.
The three blocks of a VIN
A 17-character VIN divides into three parts:
- Positions 1–3: World Manufacturer Identifier (WMI). Identifies the maker and country. For example, 1C6 and 3C6 are common on RAM trucks; 1C4 appears on many Jeep models.
- Positions 4–9: Vehicle Descriptor Section (VDS). Encodes model, body style, engine, and restraint system. Position 9 is a check digit — a calculated value that validates the whole VIN.
- Positions 10–17: Vehicle Identifier Section (VIS). Position 10 is the model year, position 11 is the assembly plant, and positions 12–17 are the sequential production number — effectively the vehicle's serial number.
Who built it: the WMI (positions 1–3)
The first three characters identify the manufacturer and the country of the building company. For FCA / Stellantis vehicles you will commonly see:
| WMI | Building company |
|---|---|
| 1C6, 1D7 | FCA US LLC (United States) |
| 2C6 | FCA Canada Inc. (Canada) |
| 3C6, 3C7, 3B7 | Chrysler de México (Mexico) |
Two cautions here, because the WMI is often misread. First, the letters do not tell you the exact assembly plant — only the manufacturing company and its country. Second, the "truck" designation baked into some WMIs is a regulatory body-style category (it even covers minivans), not proof the vehicle is a pickup. So a Canadian WMI does not mean a RAM pickup was built in Canada — Canadian FCA output is largely minivans and cars, while RAM pickups come from U.S. and Mexican plants.
The model-year code (position 10)
Model year uses a letter or number rather than the full year. The cycle skips the letters I, O, Q, U, Z and the digit 0 to avoid confusion. A few recent examples:
| Code | Model year |
|---|---|
| R | 2024 |
| S | 2025 |
| T | 2026 |
Because the codes repeat every 30 years, position 7 (numeric vs. alphabetic) is used alongside position 10 to resolve which cycle a vehicle belongs to.
The check digit (position 9)
The check digit is the VIN's built-in error detection. Each character is converted to a number, multiplied by a position weight, summed, and divided by 11; the remainder (0–9, or X for 10) must equal the character in position 9. If it does not, the VIN was mistyped or is invalid. This is why our tool requires exactly 17 characters.
The assembly plant (position 11)
Position 11 identifies the factory that built the vehicle. For current RAM trucks, the main plants are Sterling Heights Assembly in Michigan (the current-generation RAM 1500), Warren Truck Assembly in Michigan (the RAM 1500 Classic), and Saltillo in Coahuila, Mexico (RAM Heavy Duty). Jeep and other FCA models come from plants such as Toledo, Ohio and the Detroit Assembly Complex. Knowing the plant can help date a vehicle and, occasionally, understand recall applicability.
A word of caution about "plant code charts" you may find online: unlike the standardized model-year code, the single letter in position 11 is not a stable, universal plant table. The same letter can map to different plants depending on the manufacturer, model line, and year — and many charts still list plants that closed years ago. Rather than trust a generic lookup table, decode position 11 for a specific VIN with an authoritative source. The U.S. government's free NHTSA VIN decoder (vPIC) returns the actual plant for a given VIN.
Decode the rest with a build sheet
The VIN tells you the vehicle's identity, but not its full equipment list. For that, run the VIN through our build sheet lookup and read our guide on how to read a build sheet.