The GM / Chevy LM7 VORTEC 5300 is a 5.3 L (5,328 cc, 325.13 cu·in) natural aspirated V8 four-stroke liquid-cooled internal combustion gasoline engine, manufactured by General Motors since 1999 to 2007. The GM / Chevy LM7 (VIN code “T”) is a Generation III small block V8 Vortec truck engine The engine was manufactured at St. Catharines, Ontario, USA and Romulus, Michigan, USA.
This engine is a longer-stroked by 9.0 mm (0.35 in) version of the LR4 Vortec 4800. The GM / Chevy LM7 engine has a V8 cast-iron block, two aluminum heads with 16 overhead valves (OHV), and a single camshaft. This engine used a sequential fuel injection system and “Coil-Near-Plugs” ignition system and pressurized lubricating system with a wet sump. The engine is equipped with 78.0 mm (3.07 in) 3-bolts mounted throttle body.
The GM / Chevy LM7 Vortec 5.3 engine produced:
- In 1999 it produced 273 PS (201 kW; 270 HP) of peak horsepower and 427 N·m (43.5 kg·m, 314.7 ft·lb) of max. torque.
- From 2000 to 2003 the engine made 290 PS (213 kW; 285 HP) of output power and a torque rating is 441 N·m (45 kg·m, 325 ft·lb)
- The 2004-2007 engines made 299 PS (220 kW; 295 HP) of horsepower and 454 Nm (46.31 kg·m; 335.0 ft·lb) of peak torque.
General information
| Engine Specifications | |
| Engine model | GM / Chevy LM7 Vortec 5300 |
| Production | 1999-2007 |
| Engine type | 4-stroke, V8, OHV, chain driven |
| Displacement | 5.3 L (5,328 cm3, 325.13 cu·in) |
| Max. horsepower | 273 PS (201 kW; 270 HP) 290 PS (213 kW; 285 HP) 299 PS (220 kW; 295 HP) |
| Max. torque | 427 N·m (43.5 kg·m, 314.7 ft·lb) 441 N·m (45.0 kg·m, 325.0 ft·lb) 454 N·m (46.3 kg·m; 335.0 ft·lb) |
| Ignition system | Coil-Near-Plugs |
| Fuel system | Sequential fuel injection |
| Power adder | None |
| Firing order | 1-8-7-2-6-5-4-3 |
| Cooling system | Liquid-cooled |
| Lubricating system | Wet sump |
Cylinder Block
A 96.0 mm (3.78 in) cylinder bore and 92.0 mm (3.62 in) piston stroke give the LM7 engine a total of 5.3 L (325 CID) of displacement. The compression ratio rating is 9.5:1. The engine used a cast-iron cylinder block with 111.76 mm (4.40 in) of bore spacing. The Vortec 5300 is equipped with dish pistons that are made of cast aluminum alloy and powdered metal I-beam style connecting rods. The connecting rod’s length is 154.89 mm (6.098 in). Each piston is fitted with two compression rings and a single oil ring.
| Cylinder block | |
| Cylinder block alloy | Cast-iron |
| Compression ratio: | 9.5:1 |
| Cylinder bore: | 96.0 mm (3.78 in) |
| Piston stroke: | 92.0 mm (3.62 in) |
| Cylinder internal diameter (standard): | 96.000-96.018 mm (3.7795-3.7802 in) |
| Piston skirt outer diameter (standard): | 96.000 mm (3.7795 in) |
| Number of piston rings (compression / oil): | 2/1 |
| Connecting rod big end diameter (standard): | 56.505-56.525 mm (2.2246-2.2254 in) |
| Connecting rod small end diameter (standard): | 24.000 mm (0.9449 in) |
| Piston pin diameter: | 23.997-24.000 mm (0.9448-0.9449 in) |
| Side clearance (Top): | 0.040-0.085 mm (0.0016-0.0033 in) |
| Side clearance (Second): | 0.040-0.078 mm (0.0016-0.0031 in) |
| Side clearance (Oil): | 0.012-0.200 mm (0.0005-0.0079 in) |
| Ring end gap (Top): | 0.230-0.440 mm (0.0091-0.0173 in) |
| Ring end gap (Second): | 0.440-0.700 mm (0.0173-0.0276 in) |
| Ring end gap (Oil): | 0.180-0.750 mm (0.0071-0.0295 in) |
| Number of main bearings: | 5 |
| Crankshaft main journal diameter: | 64.993-65.007 mm (2.5588-2.5593 in) |
| Crankpin journal diameter: | 53.318-53.338 mm (2.0991-2.0999 in) |
| Crankshaft center distance: | 46 mm (1.81 in) |
Cylinder Head
The GM / Chevy LM7 engine has two aluminum heads with 2 valves per cylinder (16 in total) and single camshaft driven by the crankshaft via a chain. The intake port has a cathedral shape with 200 cc intake runner volume and the exhaust has an oval shape with 70 cc exhaust runner volume. Intake and exhaust valves era made of steel with a solid stem. Valves are operated via pedestal mounting rocker arms.
| Cylinder head | |
| Cylinder head alloy | Aluminium |
| Valve arrangement: | OHV, chain driven |
| Valves:: | 2 (16 valves in total) |
| Head height: | 120.2 mm (4.7323 in) |
| Intake timig: | 191° |
| Exhaust timig: | 190° |
| Valve lift (INTAKE): | 11.60 mm (0.457 in) |
| Valve lift (EXHAUST): | 11.84 mm (0.466 in) |
| Valve head diameter (INTAKE): | 48.0 mm (1.8898 in) |
| Valve head diameter (EXHAUST): | 39.4 mm (1.5512 in) |
| Valve steam diameter (INTAKE): | 7.955-7.976 mm (0.3132-0.314 in) |
| Valve steam diameter (EXHAUST): | 7.955-7.976 mm (0.3132-0.314 in) |
| Valve spring free length (INTAKE): | 52.9 mm (2.0827 in) |
| Valve spring free length (EXHAUST): | 52.9 mm (2.0827 in) |
| Camshaft lobe lift (INTAKE): | 6.96 mm (0.274 in) |
| Camshaft lobe lift (EXHAUST): | 6.82 mm (0.2685 in) |
| Camshaft journal diameter : | 54.99-55.04 mm (2.165-2.1669 in) |
Tightening torque
| Tightening torque settings | |
| Connecting rod bolts | Step 1: 20 Nm (2.04 kg·m; 14.76 ft·lb) Step 2: Turn all bolts: 70° |
| Crankshaft bearing cap bolts | Step 1: 20 Nm (2.04 kg·m; 14.76 ft·lb) Step 2: Turn inner bolts: 80° turn outer bolts: 51° |
| Flywheel bolts | Step 1: 20 Nm (2.04 kg·m; 14.76 ft·lb) Step 2: 50 Nm (5.1 kg·m; 36.9 ft·lb) Step 3: 100 Nm (10.2 kg·m; 73.8 ft·lb) |
| Cylinder head bolts | Step 1: 30 Nm (3.06 kg·m; 22.14 ft·lb) Step 2: Turn all bolts: 90° Step 3: Turn all bolts excluding the medium length bolts at the front and rear of each head: 90° Step 4: Turn all medium length bolts at the front and rear of each head: 50° |
| Valve rocker arm bolts | 30 Nm (3.06 kg·m; 22.14 ft·lb) |
Service Data
The engine oil with a viscosity of 5W-30 is recommended for the LR4, refilling oil capacity is 5.7 L (6.02 US. qt, 5.02 Imp. qt.). A recommended spark plug is AC Delco 41-985 Iridium with 1.01 mm (0.0398 in) spark plug gap.
| Oil system | |
| Lubrication system: | Wet sump |
| Oil type: | 5W-30 |
| Oil capacity: | 5.7 L (6.02 US. qt, 5.02 Imp. qt.) |
| Oil change interval: | 12,000 km (7,500 miles) |
| Fuel system | |
| Type: | Sequential multi-port fuel injection |
| Fuel Injector Flow: | 1999: 2.742 gm/sec (21.8 lb/hr) at 58 psi 2000 : 3.125 gm/sec (24.8 lb/hr) at 58 psi 2001-2007: 3.180 gm/sec (25.2 lb/hr) at 58 psi |
| Ignition system | |
| Type: | Coil-Near-Plugs |
| Spark plug: | AC Delco 41-985 Iridium |
| Spark plug gap: | 1.01 mm (0.03980.0398 in) |
| Spark plug torque: | 15 N·m (1.5 kg·m, 11.1 ft·lb) |
Applications
| Model | Years Produced |
| Chevrolet Silverado 1500 | 1999-2007 |
| Chevrolet Tahoe | 1999-2006 |
| Chevrolet Suburban 1500 | 1999-2006 |
| Chevrolet Avalanche | 2002-2006 |
| ChevroletExpress | 2003-2007 |
| GMC Sierra 1500 | 1999-2007 |
| GMC Yukon | 1999-2006 |
| GMC Yukon XL 1500 | 1999-2006 |
| GMC Savana | 2003-2007 |
| Cadillac Escalade (2WD) | 2002-2005 |
Author:
Be the first to comment