First Drive: New '07 Chevy And GMC Diesels

Manufacturing location: Pontiac and Flint, Michigan
Base price: $32,970

Engine: Duramax 6.6L, V-8 (LMM)
Displacement (ci/cc): 403/6,599
Bore and stroke (in.): 4.06 x 3.9
Block material: Cast iron
Cylinder-head material: Cast aluminum
Valvetrain: OHV
Fuel delivery: Direct-injection with high-pressure common-rail
Compression ratio: 16.8:1
Horsepower (hp @ rpm): 365 @ 3,200
Torque (lb-ft @ rpm): 660 @ 1,600
Maximum engine speed (rpm): 3,450
Fuel capacity (gal.): 34 (longbed), 26 (shortbed)

Transmission: Allison 1000 six-speed automatic with manual mode
First: 3.10 * Second: 1.81 * Third: 1.41 * Fourth: 1.00
Fifth: 0.71 * Sixth: 0.61 * Reverse: 4.49 * Rear-axle ratio: 3.73

Chassis/Suspension
Front : Long- and short-arm independent suspension with torsion bars
Rear: Semi-elliptic, two-stage, multileaf spring
Steering type: Integral power-assisted recirculating ball
Steering-gear ratio: 15-13:1 variable ratio
Steering wheel turns, lock-to-lock: 3.18
Turning circle, curb-to-curb (ft.): 45.3 (regular cab), 45.3 (Extended Cab, shortbed), 52.5 (Extended Cab, longbed), 51.2 (Crew Cab, shortbed), 55.1 (Crew Cab, longbed)

Brakes
Rotor diameter by thickness (in.): 12.8 x 1.5 (front), 12.8 x 1.2 (rear)

Tires
Tire sizes: LT245/75R16, LT265/70R17

Exterior Dimensions: Regular cab, longbed
Overall length (in.): 224.7
Overall width (in.): 79.8
Overall Height (in.): 76.3
Wheelbase (in.): 133
Track, front (in.): 68.6
Track, rear (in.): 66
Step-in height (in.): 32.4
Minimum ground clearance (in.): 9.5

TRAILER RATING
Trailer-towing maximum weight with ball hitch (lb.): 13,000 (all models)