Factory build sheet

2021 GMC Sierra Fleet/Base

Build 1GT59LEY-M · 6.6L 8cyl · Four-wheel drive · Pickup

VIN positions 1 through 8 read 1GT59LEY and position 10 reads M. Those nine characters define this build. Position 9 and positions 11 through 17 differ on every car.

Every Sierra whose VIN starts 1GT59LEY and carries M in position 10 left the plant with the same engine, transmission, drivetrain and equipment listed below. We know of 83 of them.

  • Decoded Jul 7, 2026
  • 83 known VINs
  • 3 listed for sale now

Factory specification

As filed by GMC with NHTSA for this build. Fields the filing does not record are left out entirely — a missing row means no recorded value, not a missing feature.

Engine

Displacement
6.6 L
Cylinders
8
Configuration
V-Shaped
Engine model
L5P - DI, DURAMAX, GEN 5 VAR. 1
Turbocharged
Yes
Fuel type
Diesel

Drivetrain

Drive type
Four-wheel drive
Brake system
Hydraulic

Body & chassis

Body class
Pickup
NHTSA body type
TRUCK
Cab type
Extra/Super/Quad/Double/King/Extended
Series
2500
Manufacturer
GENERAL MOTORS LLC

Weight rating

GVWR class
Class 3
GVWR
10,001–14,000 lb

Gross vehicle weight rating is the loaded ceiling set by the manufacturer, not the car's own weight.

What this build asks today

Asking prices of live dealer listings decoded to this exact configuration — narrower than the trim-level figure, because every car counted here shares the same engine, transmission and drivetrain.

$32,995 median asking price · 6 listings · as of Aug 30, 2026

Too few listings to publish a price range — with 6 cars on the market, the cheapest and the dearest are single cars, not a spread. The median above is what they ask in the middle.

Compare every 2021 Sierra trim and its price →

The same build, other model years

GMC used the VIN pattern 1GT59LEY for 4 model years. Nothing but the year changes between these pages, so the price gap between them is depreciation on an identical car.

$32,995 2021 $41,449 2022 $46,900 2024

How this VIN pattern is read

A 17-character VIN carries two kinds of information: what was built, and which one it is. This page is the first kind — the nine highlighted positions.

Positions Characters What they encode
1–3 1GT GENERAL MOTORS LLC · World manufacturer identifier
4–8 59LEY Model, body style, engine and restraint system
9 × Check digit — computed per vehicle, not part of the build
10 M Model year — 2021
11 × Assembly plant
12–17 ×××××× Production sequence number, unique to each vehicle

83 vehicles carry this build

Every VIN we have decoded to 1GT59LEY-M shares the specification above.

  • 83 Known VINs
  • 3 Listed for sale now
  • 6 Priced listings
  • $32,995 Median asking

Neighboring configurations

Other factory configurations of the Sierra, each with its own build sheet. The set is fixed by the VIN patterns themselves, so it does not shuffle as prices or inventory move.

Keep going

Where this data comes from

Specification fields are decoded from the manufacturer's filings in the NHTSA vPIC database, keyed on VIN positions 1–8 and 10. We publish the filed values as they stand and leave out anything the filing does not record.

Prices are asking prices from 6 live dealer listings decoded to this build , last updated August 30, 2026 . They are what sellers ask, not what buyers paid.

Vehicle counts come from the 83 VINs of this build we have seen in dealer inventory. They are a sample of the road population, not a production figure.