Vortec 5300 V8 (LM7)

Vortec 8100 V8 (L18)

Type:

5.3-liter V8 with cast iron block

8.1-liter V8 with cast iron block

Displacement (cu in / cc):

327 / 5358

496 / 8128

Bore & stroke (in / mm):

3.78 x 3.62 / 96 x 92

4.25 x 4.37 / 108 x 111

Cylinder head material:

cast aluminum

cast iron

Valvetrain:

overhead valves, hydraulic roller follower, two valves per cylinder, chain cam drive

hydraulic roller follower, two valves per cylinder, chain cam drive

Fuel delivery:

sequential fuel injection

sequential fuel injection

Compression ratio:

9.5:1

9.1:1

Horsepower (hp / kw @ rpm):

285 / 212.61 @ 5200

340 / 253 @ 4200

Torque (lb-ft / Nm @ rpm):

325 / 441 @ 4000

455 / 617 @ 3200

Recommended fuel:

87 octane

87 octane

Maximum engine speed (rpm):

5600

5000

Emissions controls:

three-way catalytic converter, positive crankcase ventilation, evaporative collection system

exhaust gas recirculation, Air Injection Reaction (available)

Estimated fuel economy

(mpg city / hwy / combined):

2WD: 14 / 18 / 16

4WD: 13 / 17 / 15

4L60-E

4L85-E

Type:

four-speed electronic automatic

four-speed electronic automatic

Gear ratios (:1):

First:

3.06

2.48

Second:

1.63

1.48

Third:

1.00

1.00

Fourth:

0.70

0.75

Reverse:

2.29

2.08

Axle ratio:

3.73 standard (4.10 optional)

3.73 standard (4.10 optional)

1500

2500

Front:

independent with torsion bars

independent with torsion bars

Rear:

five-link coil spring with automatic load leveling

two-stage leaf spring

Traction assist system:

part of Z66 package on 2WD models

Steering type:

2WD: power recirculating ball

2WD & 4WD: power recirculating ball

4WD: power, recirculating ball with EVO. Variable assist.

Ratio:

12.0:1

16.4:1

Steering wheel turns, lock-to-lock:

3.3

3.25

Turning circle, curb-to-curb (ft):

43.3 (2WD & 4WD)

44.1 (2WD & 4WD)