See other engines in this family
The same engine also has a main page: Chevrolet LM2.
GMC LM2 specs: 183 ci (3.0L) 6-cylinder, 3.307 x 3.543 in (84 x 90 mm) bore and stroke. Rated 277 hp, 2020–2022. Used in the GMC Sierra 1500. DOHC.
The GMC 183ci (LM2) is undersquare — the 3.5433" stroke exceeds the 3.3071" bore by 6.7% — a layout that trades peak RPM for leverage and torque low in the range. The 3.5433" stroke puts mean piston speed at 4,000 ft/min around 6,750 RPM, which is where a production bottom end is generally considered at its limit. Each of the 6 cylinders displaces 30.5 ci (500 cc).
It is one of 2 engines in the GMC 183ci family, all of them 183 ci — the differences between them are in compression, heads and rating, not displacement. 3 factory variants share these dimensions, rated at 277 hp across 2020–2022.
| Displacement | 183 ci / 3 L |
|---|---|
| Bore | 3.3071" |
| Stroke | 3.5433" |
| Cylinders | 6 |
| Configuration | I6 |
| Bore/stroke ratio | 0.933 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | DOHC |
| Fuel type | diesel |
| Advertised HP | 277 hp |
| Years | 2020–2022 |
| Bore/stroke character | 0.933 — undersquare — stroke exceeds bore, which favours low-end torque |
|---|---|
| Mean piston speed at 6,000 RPM | 3,543 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 30.5 ci |
Each link opens the calculator with this engine's specs already filled in.
These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.
| Year | Advertised HP | Code |
|---|---|---|
| 2020 | 277 hp | LM2 |
| 2021 | 277 hp | LM2 |
| 2022 | 277 hp | LM2 |