6.0L Power Stroke vs. 6.7L Cummins vs. 6.6L Duramax

6.0L Power Stroke

6.7L Cummins

6.6L Duramax LLY

Production Years:

2003 - 2007

2007.5 - present

2004 - 2006

Manufacturer:

International Navistar

Cummins

DMAX (GM, Isuzu joint venture)

Block/Head Material:

Iron/Iron

Iron/Iron

Iron/Aluminum

Configuration:

V-8

Inline 6

V-8

Displacement:

6.0 liters, 365 cubic inches

6.7 liters, 408 cubic inches

6.6 liters, 403 cubic inches

Compression Ratio:

18.0:1

17.3:1

17.5:1 (Lowered to 16.8:1 in 2006)

Bore x Stroke:

3.74 x 4.13 inches

4.21 x 4.88 inches

4.06 x 3.90 inches

Injection System:

Hydraulic electronic unit injection (HEUI)

high pressure common rail

High pressure common rail, CP3 injection pump

Aspiration:

Variable Geometry Turbocharger (VGT)

Variable geometry turbocharger (VGT)

Variable Geometry Turbocharger (VGT)

Valvetrain:

overhead cam, 4 valves per cylinder

overhead valve, 4 valves per cylinder

over head valve, 4 valves per cylinder

Weight:

approx. 966 lbs

N/A

835 lbs (approx.)

Peak Horsepower:

325 hp @ 3,300 RPM

350 hp @ 3,013 RPM

320 hp @ 3,000 RPM (2006 figures)

Peak Torque:

570 lb-ft @ 2,000 RPM

650 lb-ft. @ 1,500 RPM w/ auto trans
610 lb-ft. @ 1,500 RPM w/ man trans

560 lb-ft @ 1,600 RPM (2006 figures)

Notes:

• TorqShift transmission provides crisp, firm shifts and its Tow/Haul feature feels smarter than its competitors
• The 6.0L is highly ridiculed for questionable reliability and a number of problems

• Factory integrated exhaust brake technology
• Relatively poor fuel economy compared to its predecessor as a result of the diesel particulate filter (DPF) system
• Highest peak torque in this comparison

• First Duramax to receive advanced emissions controls
• The 2006 LLY underwent major changes that resulted in an additional 40 lb-ft of torque and 10 horsepower over previous models