A Peterbilt 378 VIN is 17 characters. Positions 1–3 say who built it and where, 4–8 describe the body and engine, 9 is a check digit, 10 is the model year, 11 is the plant, and 12–17 are the serial number. Decode a 378 VIN here and you also get its 68 recall campaigns and 3 owner complaints filed with NHTSA — free.
How to read a Peterbilt 378 VIN
Here is a real 2022 Peterbilt 378 VIN from our database, split into its parts:
VIN 1XPFDR9X8ND314531 — decoded free on its own report page.
| Position | Section | What it tells you |
|---|---|---|
| 1–3 | WMI | World Manufacturer Identifier — country, manufacturer and vehicle type. |
| 4–8 | VDS | Vehicle Descriptor Section — body style, engine, restraint system, series. |
| 9 | Check digit | A calculated digit that validates the whole VIN. Wrong digit = wrong VIN. |
| 10 | Model year | One character for the model year. Letters skip I, O, Q, U and Z. |
| 11 | Plant | The assembly plant that built the car. |
| 12–17 | Serial | Sequential production number of this exact vehicle. |
Peterbilt 378 VIN prefixes, and when each one was used
Characters 1–3 are the World Manufacturer Identifier. Every Peterbilt 378 we have on record, from 1996 to 2006, carries the same one — 1XP, which makes it a quick way to confirm you are looking at a real 378:
| VIN starts with | Years seen | Built in | Vehicle type | VINs on record |
|---|---|---|---|---|
| 1XP | 1996–2006 | United States | Truck |
Position 11 names the plant. On the Peterbilt 378 it is not one number either — assembly moved between 2 of them over the years:
| Plant code | Years active | VINs on record | Share |
|---|---|---|---|
| D | 2004–2006 | 2 | |
| N | 1996–1996 | 1 |
Counted from the 3 dated Peterbilt 378 VINs attached to NHTSA complaints — the largest such set for this model — with every code checked against the NHTSA manufacturer registry, so mistyped entries are dropped; the figures say how many records carry each code, not how many 378s left the line.
Model-year codes for the Peterbilt 378
Position 10 carries the model year, skipping I, O, Q, U and Z. The alphabet comes round every 30 years, which for the Peterbilt 378 has already happened — 1993 and 2023 share the character P. All 36 model years of the Peterbilt 378, 1988 to 2023, with the character each one carries:
| Model year | VIN character (position 10) | Same character as |
|---|---|---|
| 2023 | P | 1993 |
| 2022 | N | 1992 |
| 2021 | M | 1991 |
| 2020 | L | 1990 |
| 2019 | K | 1989 |
| 2018 | J | 1988 |
| 2017 | H | — |
| 2016 | G | — |
| 2015 | F | — |
| 2014 | E | — |
| 2013 | D | — |
| 2012 | C | — |
| 2011 | B | — |
| 2010 | A | — |
| 2009 | 9 | — |
| 2008 | 8 | — |
| 2007 | 7 | — |
| 2006 | 6 | — |
| 2005 | 5 | — |
| 2004 | 4 | — |
| 2003 | 3 | — |
| 2002 | 2 | — |
| 2001 | 1 | — |
| 2000 | Y | — |
| 1999 | X | — |
| 1998 | W | — |
| 1997 | V | — |
| 1996 | T | — |
| 1995 | S | — |
| 1994 | R | — |
When two years share a character, the check digit and serial range tell them apart — that is what the decoder does automatically.
Body and engine characters we see on Peterbilt 378 VINs
Positions 4 through 8 describe the build, and manufacturers assign them themselves — the same letter means different things on different marques. Across 6 VINs the Peterbilt 378 uses 4 different characters in these three slots alone — the ones below, ordered by how much of the Peterbilt fleet each covers:
| Position | Characters seen on real VINs | Variety |
|---|---|---|
| 4 — body | F (100%) | 1 distinct |
| 5 — series | D (83%) · X (17%) | 2 distinct |
| 8 — engine | X (100%) | 1 distinct |
A character that dominates the column usually marks the body style the model was mostly sold in; a spread across several means multiple bodies or engines shared the same platform.
What a decoded Peterbilt 378 VIN gets you
Reading the characters is the easy part — the reason to decode a VIN is what sits behind it. For the Peterbilt 378 that is 3 owner complaints and every recall campaign NHTSA has on record, keyed to the same VIN you just read:
| Data | For this model | Source |
|---|---|---|
| Recall campaigns | 68 campaigns | NHTSA |
| Owner complaints | 3 filed | NHTSA |
| Model years covered | 36 years | ForCar catalog |
Where to find the VIN on a Peterbilt 378
A Peterbilt 378 VIN normally opens with 1XP. Four places on the car carry the full number, and all four must agree — on a Peterbilt 378, a plate that disagrees is where fraud shows itself first.
| Where | How to see it | Why it matters |
|---|---|---|
| Dashboard, driver side | Through the windshield, bottom corner | Easiest to check before you touch anything |
| Driver door jamb | Open the door, sticker on the pillar | Also lists tyre pressures and build date |
| Under the hood | Firewall or strut tower plate | Survives a windshield replacement |
| Title and insurance | Paper documents | Must match the car — a mismatch means fraud or a swapped panel |
You know what it is. Find out what it's worth.
- Exact value for this VIN, adjusted for mileage
- The original window sticker and factory options
- Full research report as a PDF you can hand to a mechanic
- Decode a whole list of VINs at once
- No ads, no tracking — and much more
Frequently asked questions
Is this Peterbilt 378 VIN decoder free?
Yes — decoding a Peterbilt 378 VIN costs nothing and needs no account. Beyond the year, plant and build characters you also get what NHTSA holds on the Peterbilt 378 — 68 recall campaigns and 3 owner complaints — at no charge.
How many characters is a Peterbilt 378 VIN?
Seventeen, on every Peterbilt 378 built from 1981 onwards, when the 17-character format became mandatory in the US. The oldest Peterbilt 378 VIN on file here is a 2003, so everything in our Peterbilt data already uses the modern layout.
Why do two Peterbilt 378 model years share the same VIN character?
Position 10 cycles through the alphabet every 30 years, skipping I, O, Q, U and Z. For the Peterbilt 378 that is not theoretical: a 1993 and a 2023 both carry P in position 10, and this model was built in both years. The check digit and serial range separate them.
Can a Peterbilt 378 VIN tell me if the car was in an accident?
Not from the characters themselves — they describe how the Peterbilt 378 left the factory, not what happened to it afterwards. Crash and title records sit in separate databases keyed to the same number. What is public are the 3 complaints Peterbilt 378 owners filed with NHTSA, and those we do show. Run the number through our VIN check to see what is on the record for it.
Do the body and engine characters mean the same thing on every Peterbilt?
No, and that is the usual mistake — positions 4–8 are assigned per model, not per brand. A letter that means one body on the Peterbilt 378 can mean a different one on another Peterbilt, and something else again on another marque. On Peterbilt 378 VINs the character that dominates position 4 is F — read it against the table above, not against a generic chart.
What if the VIN on the dashboard doesn't match the door jamb?
Treat it as a red flag on any car, and on a Peterbilt 378 check the prefix first: for the model year in question it should open with 1XP, depending on when the car was built — anything outside that set did not come off a Peterbilt 378. Beyond that, mismatched plates mean either a replaced panel or a tampered identity — ask for documents and verify before any money changes hands.