Equipment unit · VIN-decoded · NHTSA vPIC

2021 Monroe Towmaster

4KNSF4631ML161789 · Trailer · TRAILER
Carriers run under1
6 mo
Inspections3
all-time
OOS inspections0
of 3
First seenOct 22, 2024
MN
Last seenApr 17, 2025
MN
01

Decoded identity

From the 17-character VIN via NHTSA vPIC

VIN
4KNSF4631ML161789
Make
Monroe Towmaster
Model
Monroe Towmaster
Model year
2021
Body class
Trailer
Vehicle type
TRAILER
GVWR
Not decoded
Decoded at
Aug 21, 2026
vPIC returns make / model / year / body class / GVWR. Fields it does not resolve are shown as Not decoded rather than guessed.
Decode evidence & sources

Deterministic structure

These fields come directly from VIN positions and the published checksum calculation, with zero store IO.

World manufacturer identifier
4KN

Deterministic · VIN positions 1–3.

Vehicle descriptor section
SF463

Deterministic · VIN positions 4–8.

Check digit
1 · valid

Deterministic · position 9; calculated value 1.

Model year candidates
1991 or 2021

Position 10 repeats every 30 years; both candidates are retained and neither is silently selected.

North American serial sequence
161789

Deterministic · positions 12–17 for a North American WMI.

Sourced platform inference

The prefix store publishes only at support ≥ 3 and purity ≥ 90%. Prefix confidence is shown beside every established platform claim.

Not established

No supported platform claim is established for this prefix

The resolver answered successfully but returned no row above the evidence floor. This does not mean the vehicle has no platform or that no data exists; it means this store cannot make the claim.

Federal observation (NHTSA vPIC)

What the federal corpus observed directly for this exact VIN — independent of, and sometimes more specific than, the prefix-level inference above.

Observed model year
2021

Observed directly for this VIN via NHTSA vPIC.

Observed make
MONROE TOWMASTER

Observed directly for this VIN via NHTSA vPIC.

Observed model
Monroe Towmaster

Observed directly for this VIN via NHTSA vPIC.

Observed body class
Trailer

Observed directly for this VIN via NHTSA vPIC.

Observed vehicle type
TRAILER

Observed directly for this VIN via NHTSA vPIC.

GVWR
Not established

Observed directly for this VIN via NHTSA vPIC.

Not established

  • platform make
  • platform model
  • model line
  • generation
  • cab type

These are withheld claims, not negative findings.

02

Inspection history

Every roadside inspection of this VIN, newest first · Oct 22, 2024 – Apr 17, 2025

DateStateLevelViol.OOSCarrier (DOT)Plate
Apr 17, 2025MNIII · Driver-only7DECOOK EXCAVATING INC 12682829475STX/MN
Mar 14, 2025MNIII · Driver-only1DECOOK EXCAVATING INC 12682829475STX/MN
Oct 22, 2024MNIII · Driver-only1DECOOK EXCAVATING INC 12682829475STX/MN
03

Carriers this unit has run under

1 distinct carrier · grouped by DOT · newest activity first

CarrierDOTFirst seenLast seenInsp.State
DECOOK EXCAVATING INC1268282Oct 22, 2024Apr 17, 20253MN
Names are left-joined from the FMCSA census; a DOT with no census match falls back to its number.
04

Plate & unit-number history

The same truck under different plate registrations across carriers

PlateState / prov.Unit no.CarrierDate rangeInsp.
9475STXMN2DECOOK EXCAVATING INCOct 22, 2024Apr 17, 20253
Sources: FMCSA SAFER · L&I · NHTSA vPIC · decoded Aug 21, 2026