GMC LM7 / L59 Specs: 3.78 x 3.622 in, 285-295 hp

See other engines in this family

GMC LM7 / L59 specs: 325 ci (5.3L) 8-cylinder, 3.78 x 3.622 in (96 x 92 mm) bore and stroke. Rated 285-295 hp, 2002–2006.

The GMC LM7 / L59 is close to square: 3.7799" bore against 3.622" stroke, within 4.4%, which splits the difference between a high-revving layout and a torque layout. 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 40.6 ci (666 cc).

It is one of 15 engines in the GMC 325ci family, all of them 325 ci — the differences between them are in compression, heads and rating, not displacement. 5 factory variants share these dimensions, rated from 285 to 295 hp across 2002–2006.

Dimensions

Displacement	325 ci / 5.3 L
Bore	3.7799"
Stroke	3.622"
Cylinders	8
Configuration	V8
Bore/stroke ratio	1.044

Construction

Block material	aluminum
Head material	aluminum
Valvetrain	OHV
Fuel type	gas
Advertised HP	285–295 hp
Years	2002–2006

Factory ratings by year

Year	Version	HP @ rpm	Torque @ rpm	Comp.
2002	LM7 / LM7 / L59 net	285 @ 5200 *	325 lb-ft @ 4000 *	—
2003	LM7 / LM7 / L59 net	285 @ 5200 *	325 lb-ft @ 4000 *	—

Factory specification sheet. * Not yet cross-verified.

What these numbers mean

Bore/stroke character	1.044 — square — bore and stroke are within 5%, a balanced compromise
Mean piston speed at 6,000 RPM	3,622 ft/min — in the range typical of performance street engines
Displacement per cylinder	40.6 ci

Run the numbers for this engine

Each link opens the calculator with this engine's specs already filled in.

• Displacement from bore and stroke (calculator)
• Static and dynamic compression ratio calculator
• Piston ring gap for this bore
• Piston speed at any RPM
• Horsepower to torque at any RPM
• What size carburetor (CFM calculator)

Variants sharing these dimensions (5)

These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.

Year	Advertised HP	Code
2002	285 hp	LM7 / L59
2003	285 hp	LM7 / L59
2004	295 hp	LM7 / L59
2005	295 hp	LM7 / L59
2006	295 hp	LM7 / L59

What cars have the LM7 / L59?

11 factory vehicles, 1999–2007. Each year opens that model's engine table.

• Chevrolet Silverado 1500: 1999, LM7, 270 hp; 2000, LM7, 285 hp; 2001, LM7, 285 hp; 2002, LM7, 285 hp; 2003, LM7, 285 hp; 2004, LM7, 295 hp; 2005, LM7, 295 hp; 2006, LM7, 295 hp; 2006, L59, 295 hp; 2007, LM7, 295 hp; 2007, L59, 295 hp
• Chevrolet Silverado HD: 1999, LM7, 270 hp; 2000, LM7, 285 hp
• GMC Sierra 1500: 1999, LM7, 270 hp; 2000, LM7, 285 hp; 2001, LM7, 285 hp; 2002, LM7, 285 hp; 2003, LM7, 285 hp; 2004, LM7, 295 hp; 2005, LM7, 295 hp; 2006, LM7, 295 hp; 2007, LM7, 295 hp
• GMC Sierra HD: 1999, LM7, 270 hp; 2000, LM7, 285 hp
• GMC Yukon: 2000, LM7, 285 hp; 2001, LM7, 285 hp; 2002, LM7 / L59, 285 hp; 2003, LM7 / L59, 285 hp; 2004, LM7 / L59, 295 hp; 2005, LM7 / L59, 295 hp; 2006, LM7 / L59, 295 hp
• Chevrolet Suburban: 2000, LM7, 285 hp; 2001, LM7, 285 hp; 2002, LM7, 285 hp; 2002, L59, 285 hp; 2003, LM7, 285 hp; 2003, L59, 285 hp; 2004, LM7, 295 hp; 2004, L59, 295 hp; 2005, LM7, 295 hp; 2005, L59, 295 hp; 2006, LM7, 295 hp; 2006, L59, 295 hp
• Chevrolet Tahoe: 2000, LM7, 285 hp; 2001, LM7, 285 hp; 2002, LM7 / L59, 285 hp; 2003, LM7 / L59, 285 hp; 2004, LM7 / L59, 295 hp; 2005, LM7 / L59, 295 hp; 2006, LM7 / L59, 295 hp
• Cadillac Escalade: 2002, LM7, 285 hp; 2003, LM7, 285 hp; 2004, LM7; 2005, LM7
• Chevrolet Avalanche: 2002, LM7, 285 hp; 2003, L59; 2003, LM7, 285 hp; 2004, LM7, 295 hp; 2005, L59; 2005, LM7, 295 hp; 2006, L59; 2006, LM7, 295 hp
• Chevrolet Chevy Van / Express: 2003, LM7; 2004, LM7; 2005, LM7; 2006, LM7; 2007, LM7
• GMC Vandura / Savana: 2003, LM7; 2004, LM7; 2005, LM7; 2006, LM7; 2007, LM7

Similar engines

• GMC LH8 — 325 ci
• GMC LH9 — 325 ci
• GMC LM4 — 325 ci
• GMC LH6 — 325 ci
• GMC LM7 — 325 ci
• GMC L33 — 325 ci
• Chevrolet L83 — 325 ci
• Chevrolet L83 — 325 ci

← All GMC 325ci engines