5.3L Engine

5.3 L

The Vortec 5300, or LM7/L59/LM4, is a V8 truck engine. It is a longer-stroked (by 9 mm (0.35 in)) version of the Vortec 4800 and replaced the L31. L59 denoted a flexible fuel version of the standard fuel LM7 engine. Displacement is 5.3 L (5,328 cc (325.1 cu in)) from 3.78-inch (96 mm) bore and 3.622-inch (92.0 mm) stroke. Another engine variant, the L33, shares the same displacement, but has an aluminum block with cast in cylinder liners, much like the LS1. This allowed a 100 lb (45 kg) weight savings over the standard LM7 model. Other differences were a higher lift cam shaft (0.482 in (12.2 mm) v. 0.456 in (11.6 mm) on both intake & exhaust), higher compression ratio (9.9:1 v. 9.49:1), and cylinder heads originally designed for the LS6. These differences bumped output: GM rated the engine at 315 hp (235 kW) and 338 lbf·ft (458 N·m).

LM7

The Vortec 5300 LM7 (VIN code 8th digit "T") was introduced in 1999, and can be considered the "garden variety" version of the Generation III 5.3 liter V8's. The 1999 LM7 engine produced 270 hp (201 kW) and 315 lb·ft (427 N·m), 2000-2003 engines made 285 hp (213 kW) and 325 lb·ft (441 N·m). The 2004-2007 engines made 295 hp (220 kW) and 335 lb·ft (454 N·m), it has a cast iron block and aluminum heads.

LM7 applications:

2002–2005 Cadillac Escalade 2WD1

2002–2006 Chevrolet Avalanche

2003–2007 Chevrolet Express/GMC Savana

1999–2007 Chevrolet Silverado 1500

1999–2007 GMC Sierra 1500

2000–2006 Chevrolet Suburban/GMC Yukon XL

2000–2006 Chevrolet Tahoe/GMC Yukon

L59

The Vortec 5300 L59 (VIN code "Z") is a flexible fuel version of the LM7. The 2002-2003 made 285 hp (213 kW) and 320 lb·ft (434 N·m), while the 2004-2007 L59s made 295 hp (220 kW) and 335 lb·ft (454 N·m).

L59 applications:

2002–2007 Chevrolet Silverado 1500 Chevrolet Avalanche Z71 Package

2002–2006 Chevrolet Tahoe/GMC Yukon

2002–2006 Chevrolet Suburban/GMC Yukon XL

2002–2007 GMC Sierra 1500

LM4

The Vortec 5300 LM4 (VIN code "P") is an aluminum block version of the LM7, and had a short production life. The LM4s made 290 hp (216 kW) and 325 lb·ft (441 N·m), It should not be confused with the L33 described below.

LM4 applications:

2003–2004 Chevrolet TrailBlazer EXT

2003–2004 Isuzu Ascender

2004 GMC Envoy XL

2003–2004 Chevrolet SSR

2004 Buick Rainier

L33

The Vortec 5300 L33 (VIN code "B") is an aluminum block version of the LM7, and was referred to as the Vortec 5300 HO in marketing materials. However it should be noted that the L33 uses a flat top piston from the 4.8L instead of the standard dish piston found in the LM7. It also uses 799 cylinder heads, which are identical to the 243 casting found on the LS6 and LS2 with the exception to the Corvette spec valve springs, and hollow stem exhaust valves on the 2002-2004 LS6. This combination increased the compression from 9.5:1 to 10.0:1. Also the L33 had a specific camshaft not shared with any other engine, with lobe lift of 7.2 mm, 193 degrees of intake and exhaust duration, and a 116 degree lobe separation angle. As a result power increased by 15 hp (11 kW), to 310 hp (230 kW) and 335 lb·ft (441 N·m). It was only available on extended cab 4WD pickup trucks. Only 25% of trucks made in 2005 had the L33 engine.

L33 applications:

2005–2007 Chevrolet Silverado 1500 4WD

2005–2007 GMC Sierra 1500 4WD