Commercial Truck Engine

Cummins B6.7H (hydrogen, 2027+)

6.70L Inline-6 hydrogen ICE • Cummins

Production 2027–present Class 6-7 240–320 hp

In production

Displacement

6.70L

Configuration

Inline-6 hydrogen ICE

Power range

240–320 hp

Production

2027–present

About the Cummins B6.7H (hydrogen, 2027+)

The Cummins B6.7H is Cummins' hydrogen-fueled internal combustion engine (H2-ICE) for medium-duty trucks — launching for the 2027 model year. Hydrogen ICE is different from fuel-cell electric: it burns H2 in a conventional combustion chamber (like diesel or natural gas) rather than using a fuel-cell stack to generate electricity. Same B6.7 block architecture as diesel B6.7 and the B6.7N natural-gas version. H2-ICE produces near-zero tailpipe emissions (only water vapor + trace NOx from high combustion temperatures). Part of Cummins' HELM fuel-agnostic platform strategy.

Overview

Specifications

Manufacturer: Cummins
Displacement: 6.70 liters
Configuration: Inline-6 hydrogen ICE
Fuel type: Hydrogen (H2 interna
Horsepower: 240–320 hp
Torque: 600–750 lb-ft
Production years: 2027–present
Truck classes: Class 6-7
Applications: Medium-duty regional, urban delivery, severe-duty service body (zero-carbon)

Design and engineering

6.7L inline-6 hydrogen ICE. Spark ignition. Modified head and injection system for H2. Aftertreatment is much simpler than diesel (no DPF, no DEF, only NOx control).

Generations and emissions eras

B6.7H Launch

2027–present

First-generation hydrogen ICE.

Reliability and longevity

Too new for any real-world data. Cummins has been testing H2-ICE prototypes since 2022.

Common problems

Unknown. Hydrogen fueling infrastructure is the biggest barrier.

Pros and cons

✓ Pros

• Near-zero carbon when using green H2
• Same maintenance familiarity as diesel
• Cheaper than fuel-cell electric (FCEV)
• Cummins HELM platform integration

⚠ Cons

• Hydrogen fueling infrastructure gap
• Higher H2 cost vs diesel
• Range limitations — H2 storage is bulky
• Brand-new technology — long-term unknowns

Trucks that use this engine

Freightliner M2Class 6-8 Kenworth T370Class 7 Mack MD6 / MD7 (medium-duty)Class 6-7 Peterbilt 337Class 7

Frequently Asked Questions

What is the Cummins B6.7H (hydrogen, 2027+)?

What trucks use the Cummins B6.7H (hydrogen, 2027+)?

The Cummins B6.7H (hydrogen, 2027+) is used in 4 truck models we cover: Freightliner M2, Kenworth T370, Mack MD6 / MD7 (medium-duty), Peterbilt 337. It primarily appears in Class 6-7 applications for Medium-duty regional, urban delivery, severe-duty service body (zero-carbon).

Is the Cummins B6.7H (hydrogen, 2027+) reliable?

Too new for any real-world data. Cummins has been testing H2-ICE prototypes since 2022.

What are the common problems with the Cummins B6.7H (hydrogen, 2027+)?

Unknown. Hydrogen fueling infrastructure is the biggest barrier.

How does the Cummins B6.7H (hydrogen, 2027+) compare to competitors?

Cummins B6.7H (hydrogen, 2027+) competes with other major commercial diesel engines including Cummins B6.7, Ford Power Stroke 6.7L, and Duramax 6.6L. Each has different strengths in fuel economy, reliability, parts availability, and resale impact. See the pros and cons section above for specific comparisons.

What's the resale impact of buying a truck with the Cummins B6.7H (hydrogen, 2027+)?

Engine choice significantly affects truck resale value. Cummins-equipped trucks typically command the highest resale premium across all manufacturers, while emerging engines (International A26) or troubled legacy engines (MaxxForce 13) command lower resale.

Operating Cummins B6.7H (hydrogen, 2027+)-equipped trucks? Talk to us.

(682) 978-8641 Send a message