What DMAX does

DMAX, Ltd. is a private 60:40 joint venture between General Motors (60%) and Isuzu Motors, Ltd. (40%), operating since 2000 as a dedicated Tier-1 OEM manufacturer of the Duramax 6.6L V-8 turbo-diesel engine. Its entire output is supplied exclusively to GM's heavy-duty pickup platforms — Chevrolet Silverado HD and GMC Sierra — with finished engines shipped to GM's Flint, Michigan assembly plant. The company runs a primary 540,000-square-foot manufacturing facility in Moraine, Ohio, supplemented by a 251,000-square-foot Brookville, Ohio plant (completed 2020) that machines engine blocks and cylinder heads for vertical-integration into final assembly.

Core technology centers on the Duramax 6.6L platform, currently in the L5P generation producing 445 hp at 2,800 rpm and 910 lb-ft of torque at 1,600 rpm. DMAX highlights a proprietary fuel-injection system that reduces noise and emissions, a rigid block design that lowers operational noise (38% idle-noise reduction versus predecessor), and an 8-minute hot-test cycle performed on every engine for performance and diagnostics validation. Quality systems include IATF 16949 (formerly TS 16949), ISO 14001, and BIQ4 certification (achieved March 2022). Cumulative production exceeded 3 million engines as of April 2023.

The business model is straightforward OEM hardware supply: DMAX produces engines on contract for GM, with pricing not publicly disclosed and no direct-to-consumer distribution, aftermarket sales, or diversification to non-GM customers. The company employs approximately 800 people (670 hourly represented by IUE-CWA Local 755, 126 salaried) plus ~100 at Brookville. Revenue, margins, and unit volumes are not publicly reported — DMAX is consolidated within GM's powertrain operations and Isuzu's equity-method investments rather than reported as a standalone entity. End customers are heavy-duty truck buyers and commercial fleet operators whose value drivers are towing capacity (up to 35,500 lb), durability, and refinement.

Name

DMAX

Legal name

DMAX, Ltd.

Website

https://dmaxengines.com

Company type

Private

Founded year

1998

Operating status

Operating

Headcount range

251–500 employees

Short description

DMAX, Ltd. is a 60:40 GM/Isuzu joint venture that exclusively manufactures the Duramax 6.6L V-8 turbo-diesel engine for General Motors' Chevrolet Silverado HD and GMC Sierra heavy-duty pickup trucks, operating from Ohio facilities.

Ownership category

akta.pro rank

Product category

Diesel Engine Manufacturing

NAICS

Engine, Turbine, and Power Transmission Equipment Manufacturing (3336)

SIC

Engines & Turbines (3510)

akta.pro primary industry

Truck & Commercial Vehicle Powertrain Manufacturing (Diesel/CNG/Hydrogen/Hybrid) (IMACABAJ)

akta.pro secondary industry

Pickup Truck Manufacturing (Commercial/Work Configurations) (IMACABAD)

Keywords

• Diesel engine manufacturing
• OEM engine supplier
• Turbo-diesel powertrains
• Heavy-duty truck engines
• Automotive manufacturing

Headquarters

HQ city

Ohio City

HQ country

United States

HQ region

North America

Offices4 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Operations, Supply Chain, Infrastructure, Technology or R&D

Revenue model

1. Diesel Engine Manufacturing: DMAX produces Duramax 6.6L V-8 turbo-diesel engines exclusively for General Motors vehicles (GMC Sierra and Chevrolet Silverado HD). The company operates as a 60:40 joint venture between GM and Isuzu, with revenue generated through OEM engine supply contracts with GM.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels1 record

Core offering

DMAX Ltd. manufactures the Duramax 6.6L V-8 turbo-diesel engine as original equipment exclusively for General Motors' GMC Sierra HD and Chevrolet Silverado HD heavy-duty pickup trucks. Production occurs at a 540,000 sq ft facility in Moraine, Ohio, supplemented by a 251,000 sq ft block and head machining plant in Brookville, Ohio. Every engine is cycled through an 8-minute hot test for performance, diagnostics, and function verification prior to shipment.

Product overview

DMAX Ltd is a 60:40 joint venture between General Motors and Isuzu Motors, operating as a manufacturing company that produces the Duramax 6.6L V-8 turbo-diesel engine. The company's product portfolio centers on the Duramax engine family, including the L5P series launched in 2016/2017, which powers GMC Sierra and Chevrolet Silverado HD heavy-duty pickup trucks. The engines are manufactured at the company's Ohio facility and feature proprietary fuel injection systems and rigorous hot-test quality control processes.

Differentiator

Problem solved

Functional benefit

Products and services

• Duramax 6.6L V-8 Turbo-Diesel Engine Heavy-duty 6.6-liter V-8 turbo-diesel engine offered as original equipment on GMC Sierra HD and Chevrolet Silverado HD pickup trucks, producing SAE-certified 445 horsepower (332 kW) at 2,800 RPM and net 910 lb-ft (1,234 Nm) of torque at 1,600 RPM. Features a proprietary fuel injection system and rigid block design that reduce noise and emissions while supporting up to 35,500 lbs of towing capacity.
• Duramax L5P Engine Series Current-generation Duramax 6.6L V-8 turbo-diesel engine launched in 2016/2017 as the L5P series, featuring improved cooling for handling higher loads. Pairs with Allison 10-speed automatic transmissions in Chevrolet Silverado and GMC Sierra heavy-duty trucks, including medium-duty Silverado 4500HD/5500HD/6500HD applications.
• DMAX Manufacturing Services OEM diesel engine production services operated from DMAX's 540,000 sq ft Moraine, Ohio manufacturing facility, with each engine cycled through an 8-minute hot test that performs strict engine performance, diagnostics, and function verification prior to shipment. Complemented by the 251,000 sq ft Brookville, Ohio block-and-head machining plant and reliability engineering offices in Michigan.

Named customers2 records

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

Six partnerships are on record, tiered core and minor.

• General MotorscoreStrategic or Co-development Partner · 1 January 1998DMAX is a 60:40 joint venture between General Motors (60%) and Isuzu Motors, Ltd. (40%). GM is the majority owner and primary customer, with DMAX producing Duramax engines exclusively for GM vehicles.
• Isuzu Motors, Ltd.coreStrategic or Co-development Partner · 1 January 1998Isuzu holds 40% ownership in the DMAX joint venture with General Motors. Isoku executive Jay Nijima stated the partnership ensures they meet great customer demand.
• IUE-CWA Local 755coreOthersThe manufacturing workforce at DMAX is represented by IUE-CWA Local 755 union. The union supports apprenticeship programs with local high schools and participates in joint leadership meetings with management.
• Workhorse Group, Inc.minorOthersGM was in discussions to sell the Lordstown Complex to Workhorse Group, Inc., a Cincinnati-based manufacturer of battery electric vehicles that could bring production and EV assembly jobs to the Mahoning Valley.
• Montgomery County (Ohio)minorOthersMontgomery County approved a $400,000 ED/GE (Economic Development/Government Equity) grant to support the GM DMAX Brookville plant development.
• City of BrookvilleminorOthersCity of Brookville worked with GM to locate the new DMAX expansion plant, providing economic development support and incentives.

Scale indicators14 records

Recent moves8 records

Expansion highlights3 records

Emerging players

• Weichai Power: Weichai is one of the world's largest diesel engine manufacturers, with heavy-duty engine families used in commercial trucks in China and export markets. Comparable in diesel engine scale and powertrain expertise, primarily competing outside North America but increasingly relevant in global HD segments.
• Yanmar: Yanmar manufactures diesel engines across industrial, marine, agricultural, and commercial vehicle applications, with growing HD engine offerings. Comparable in diesel engine technology, but more focused on smaller displacement and off-highway than on-highway HD pickups.

Broad incumbents

• Ford Power Stroke (in-house engine operations): Ford's Power Stroke 6.7L V-8 turbo-diesel competes directly with the Duramax in Super Duty F-250/F-350. While not a separate 'engine company,' Ford's in-house HD diesel engine program is the closest competing OEM-internal powertrain to DMAX's role within GM.
• Isuzu Motors: Isuzu is the 40% owner of DMAX and one of the world's largest manufacturers of commercial diesel engines and trucks. Comparable through overlapping diesel engine technology, though Isuzu's primary markets are commercial medium-duty trucks globally rather than North American HD pickups.

Direct peers

• Cummins Inc. Cummins is the largest independent heavy-duty diesel engine manufacturer in North America, with its 6.7L Cummins Turbo Diesel directly competing against the Duramax 6.6L in the heavy-duty pickup segment (e.g., Ram 2500/3500). It is the most direct competitor to DMAX's core product.
• Detroit Diesel (Daimler Truck): Detroit Diesel, a Daimler Truck subsidiary, manufactures heavy-duty diesel engines (DD15, DD13, DD8) for Class 6-8 commercial trucks. Highly comparable in diesel engine technology, scale, and OEM-supply model even though it serves Daimler-internal platforms rather than pickups.
• Navistar / International (Traton): Navistar manufactures medium- and heavy-duty trucks and proprietary diesel engines (A26) for vocational and commercial applications. Comparable as an OEM-aligned engine supplier in the HD truck space with integrated powertrain operations.
• Volvo Group Powertrain: Volvo Group's Powertrain division develops and manufactures heavy-duty diesel engines (D13, D11) for Volvo Trucks, Mack, and Renault Trucks. Comparable as an OEM-affiliated HD diesel powertrain manufacturer with significant scale and emissions-regulatory focus.
• PACCAR: PACCAR is the parent of Kenworth and Peterbilt and has direct diesel powertrain operations through PACCAR Powertrain (MX-11, MX-13). Comparable in the heavy-duty truck engine space as an integrated OEM/engine supplier, though oriented toward Class 6-8 rather than pickups.

Others

• Caterpillar (Cat Power & Propulsion): Caterpillar manufactures large diesel and gas engines for industrial, marine, oil and gas, and rail applications. Adjacent rather than competitive—it does not produce on-highway HD truck engines competing with Duramax, but is comparable as a major diesel engine manufacturer with similar powertrain engineering scale.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

• Facebookfacebook.com/profile.php

Compliance2 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about DMAX