Factory build sheet
2021 GMC Sierra Fleet/Base
Build 1GT28LE7-M · 6.6L 8cyl · Pickup
VIN positions 1 through 8 read 1GT28LE7 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 1GT28LE7 and carries M in position 10 left the plant with the same engine, transmission, drivetrain and equipment listed below. We know of 17 of them.
- Decoded Sep 9, 2026
- 17 known VINs
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
- Engine model
- L8T - SIDI, VVT, CAST IRON
- Fuel type
- Gasoline
Drivetrain
- Drive type
- 4x2
- 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 2H
- GVWR
- 9,001–10,000 lb
Gross vehicle weight rating is the loaded ceiling set by the manufacturer, not the car's own weight.
The same build, other model years
GMC used the VIN pattern 1GT28LE7 for 3 model years. Nothing but the year changes between these pages, so the price gap between them is depreciation on an identical car.
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 | 28LE7 | 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 |
17 vehicles carry this build
Every VIN we have decoded to 1GT28LE7-M shares the specification above.
- 17 Known VINs
- 1GT28LE7 5MF289825
- 1GT28LE7 XMF274396
- 1GT28LE7 4MF274295
- 1GT28LE7 1MF295850
- 1GT28LE7 6MF274332
- 1GT28LE7 6MF275092
- 1GT28LE7 7MF256096
- 1GT28LE7 2MF274764
- 1GT28LE7 5MF274340
- 1GT28LE7 1MF256224
- 1GT28LE7 2MF282797
- 1GT28LE7 0MF275055
- 1GT28LE7 XMF274219
- 1GT28LE7 0MF256957
- 1GT28LE7 0MF135703
- 1GT28LE7 9MF274356
- 1GT28LE7 3MF275065
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.
Vehicle counts come from the 17 VINs of this build we have seen in dealer inventory. They are a sample of the road population, not a production figure.