See other engines in this family
The same engine also has a main page: Chevrolet L86.
GMC L86 specs: 376 ci (6.2L) 8-cylinder, 4.065 x 3.622 in (103.3 x 92 mm) bore and stroke. Rated 420 hp, 2014–2018. Used in the GMC Sierra 1500. OHV.
The GMC 376ci (L86) is oversquare — the 4.065" bore exceeds the 3.622" stroke by 12.2% — a layout that favors airflow and RPM over leverage at the crank. The 3.622" stroke puts mean piston speed at 4,000 ft/min around 6,650 RPM, which is where a production bottom end is generally considered at its limit. Each of the 8 cylinders displaces 47.0 ci (770 cc).
It is one of 4 engines in the GMC 376ci family, all of them 376 ci — the differences between them are in compression, heads and rating, not displacement. 5 factory variants share these dimensions, rated at 420 hp across 2014–2018.
| Displacement | 376 ci / 6.2 L |
|---|---|
| Bore | 4.065" |
| Stroke | 3.622" |
| Cylinders | 8 |
| Configuration | V8 |
| Bore/stroke ratio | 1.122 |
| Block material | aluminum |
|---|---|
| Head material | aluminum |
| Valvetrain | OHV |
| Fuel type | gas |
| Advertised HP | 420 hp |
| Years | 2014–2018 |
| Bore/stroke character | 1.122 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,622 ft/min — in the range typical of performance street engines |
| Displacement per cylinder | 47.0 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 |
|---|---|---|
| 2014 | 420 hp | L86 |
| 2015 | 420 hp | L86 |
| 2016 | 420 hp | L86 |
| 2017 | 420 hp | L86 |
| 2018 | 420 hp | L86 |