My Cart

Checkout

Customers also purchased

Subtotal
$0.00
Checkout

L7

LM7 Vortec 5.3L V8 "GEN III"

Vehicle Applications

  • 1999–2007 Chevrolet Silverado 1500
  • 1999–2007 GMC Sierra 1500
  • 2000–2006 Chevrolet Tahoe
  • 2000–2006 Chevrolet Suburban 1500
  • 2000–2006 GMC Yukon 
  • 2000–2006 GMC Yukon XL 1500
  • 2002–2005 Cadillac Escalade
  • 2002–2006 Chevrolet Avalanche
  • 2003–2007 Chevrolet Express
  • 2003–2007 GMC Savana

Product Highlights

  • Gen III Iron Cylinder Block
  • Cathedral Port Aluminum Cylinder Heads
  • Drive By Cable (Mechanical Throttle) 1999-2002
  • Drive By Wire (Electronic Throttle) *phased in on most 2003+ models
  • 24X Ignition Systems



LM7 Engine Specs (VIN 'T")

The information listed here is for the stock engine.

Performance Specifications
Compression
Ratio		 9.5:1
Horsepower
Rating		 270-295 hp
Torque
Rating		 315-335 ft.-lbs.

 

Application Information

VIN 8th Digit

Year

Make

Model

T

1999-2007

Chevrolet

Silverado 1500

GMC

Sierra 1500

1999-2006

Chevrolet

Tahoe

Suburban 1500

GMC

Yukon

Yukon XL 1500

2002-2005

Cadillac

Escalade (2WD)

2002-2006

Chevrolet

Avalanche

2003-2007

Chevrolet

Express

GMC

Savana

 

Engine Block Specifications
Casting
Numbers

12567392, 12567393, 12551358
Material

Iron
Displacement

5.3L / 325 cid
Bore
Dia.

3.780 in.
Stroke

3.622 in.
Deck
Height

9.230-9.240 in.
Bore
Spacing

4.400 in.
Thrust
Bearing Location

#3 Main
Main
Cap Style

6-Bolt
Main
Housing Bore Diameter

2.751 in.
Cam Housing Bore Diameter

Bore 1/5 = 2.326, Bore 2/4 = 2.317, Bore 3 = 2.307 (1999-2003)

Bore 1/5 = 2.346, Bore 2/4 = 2.326, Bore 3 = 2.307 (2003-2007)
Cam-to-Crank
Centerline

4.914 in.

 

Rotating Assembly Specifications
Piston Material

Hypereutectic Cast Aluminum Alloy
Piston
Style

Dished
Piston Volume

+8cc
Wrist Pin Dia. (1999-2004)

0.9447 in., 0.9448 in. (Pressed)
Wrist Pin Dia. (2005-2007)

0.9429 in., 0.9431 in (Floating)
Connecting Rod Material

Powdered Metal
Connecting Rod Style

I-Beam
Connecting Rod Length

6.098 in.
Connecting Rod Bolts

M9 x 1 x 43
Crankshaft Material

Cast Iron
Crankshaft Main Journal

2.559 in.
Crankshaft Rod Journal

2.100 in.
Reluctor Wheel

24x
Flexplate Mounting Flange
(1999-2007)

0.857 in.

 

Cylinder Head Specifications
Casting
Numbers

862,706
Material

Aluminum
Combustion Chamber Volume

61cc
Intake
Port Shape

Cathedral
Intake
Runner Volume

200cc
Exhaust
Port Shape

Oval
Exhaust Runner Volume

70cc
Intake
Valve Diameter

1.890 in.
Exhaust
Valve Diameter

1.550 in.
Cylinder
Head Bolt Style

Torque to Yield (TTY)
Cylinder
Head Bolt Size (1999-2003)

(8) M11 x 2 x 155, (2) M11 x 2 x 100, (5) M8 x 1.25 x 45
Cylinder Head Bolt Size
(2004-2006)

(10) M11 x 2 x 100, (5) M8 x 1.25 x 45

 

Camshaft Specifications
Years

1999

2000-2006
Duration
at .050 in (int./exh)

191/190

191/190
Valve
Lift (int./exh)

0.457 in./0.466 in.

0.457 in./0.466 in.
Lobe
Separation Angle (in degrees)

115.5

114
Cam
Gear Attachment

3-Bolt

3-Bolt

 

Valvetrain Specifications
Lifter
Style

Hydraulic Roller
Lifter
Link Style

Plastic Lifter Tray
Lifter
Body Diameter

0.842 in.
Pushrod
Length

7.385 in.
Rocker
Arm Mounting Style

Pedestal
Rocker
Arm Style

Die-Cast, Roller Fulcrum
Rocker
Ratio

1.7
Rocker
Offset

None
Valve
Spring Style

Beehive
Valve
Spring Color

Natural
Valve
Angle

15 Degrees
Intake
Valve Material

Steel - Solid Stem
Intake
Valve Dia.

1.890 in.
Exhaust
Valve Material

Steel - Solid Stem
Exhaust
Valve Dia.

1.550 in.

 

Other Specifications
Intake
Manifold

Truck Style
Throttle
Body

78mm, 3-Bolt
Throttle Control

All Cable Operated, 1999-2002

Drive-by-Wire *phased in on most 2003+ models
Fuel
Injector Flow

1999 = 21.8 lb/hr @ 58 psi

2000 = 24.8 lb/hr @ 58 psi

2001-07 = 25.2 lb/hr @ 58 psi
Fuel
Injector Length (between O-Rings)

1.900 in.
Fuel
Injector Connector

Mini-Delphi / Multec2
PCM

Warren
Crankshaft
Reluctor Ring

24x
Camshaft
Sensor

Rear Mount, 1x on cam
Oil
Pan

Deep Rear Sump
Oil
Pump

Standard Volume



LM7 Harnesses