Factory build sheet
2012 GMC Sierra SLT
Build 1GT221C8-C · 6.6L 8cyl · Four-wheel drive · Pickup
VIN positions 1 through 8 read 1GT221C8 and position 10 reads C. Those nine characters define this build. Position 9 and positions 11 through 17 differ on every car.
Every Sierra whose VIN starts 1GT221C8 and carries C in position 10 left the plant with the same engine, transmission, drivetrain and equipment listed below. We know of 28 of them.
- Decoded Jul 7, 2026
- 28 known VINs
- 2 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
- LML
- Engine manufacturer
- DURAMAX
- Turbocharged
- Yes
- Fuel type
- Diesel
Drivetrain
- Drive type
- Four-wheel drive
- Brake system
- Hydraulic
Body & chassis
- Body class
- Pickup
- NHTSA body type
- TRUCK
- Doors
- 2
- 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 1GT221C8 for 3 model years. Nothing but the year changes between these pages, so the price gap between them is depreciation on an identical car.
- 2011 SLT 6.6L 8cyl Pickup · 116 vehicles code B
-
2012 You are here code C
- 2013 SLT 6.6L 8cyl Pickup · 97 vehicles code D $25,175
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 | 221C8 | Model, body style, engine and restraint system |
| 9 | × | Check digit — computed per vehicle, not part of the build |
| 10 | C | Model year — 2012 |
| 11 | × | Assembly plant |
| 12–17 | ×××××× | Production sequence number, unique to each vehicle |
28 vehicles carry this build
Every VIN we have decoded to 1GT221C8-C shares the specification above.
- 28 Known VINs
- 2 Listed for sale now
- 1GT221C8 1CZ255847
- 1GT221C8 XCZ310540
- 1GT221C8 9CZ303482
- 1GT221C8 6CZ277925
- 1GT221C8 7CZ109890
- 1GT221C8 8CZ291423
- 1GT221C8 0CZ280125
- 1GT221C8 9CZ298297
- 1GT221C8 8CZ308527
- 1GT221C8 4CZ213009
- 1GT221C8 5CZ147523
- 1GT221C8 7CZ219032
- 1GT221C8 4CZ287952
- 1GT221C8 3CZ171853
- 1GT221C8 1CZ216921
- 1GT221C8 2CZ199580
- 1GT221C8 5CZ260825
- 1GT221C8 XCZ254003
- 1GT221C8 6CZ137275
- 1GT221C8 0CZ246654
- 1GT221C8 4CZ304457
- 1GT221C8 5CZ233057
- 1GT221C8 5CZ155251
- 1GT221C8 7CZ224960
- 1GT221C8 8CZ304879
- 1GT221C8 7CZ284494
- 1GT221C8 7CZ308048
- 1GT221C8 5CZ237285
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.
Vehicle counts come from the 28 VINs of this build we have seen in dealer inventory. They are a sample of the road population, not a production figure.