Magnum Diesel Parts

What Magnum Diesel Parts does

Magnum Diesel Parts, Inc. is a privately held B2B supplier of sealing components, gasket sets, and engineered products for the heavy-duty diesel aftermarket, founded in 2003 and headquartered in Riverside, California. The company serves engine rebuilders, independent repair shops, and parts distributors operating across construction, mining, marine, oil field, over-the-road trucking, and stationary engine applications, with sealing solutions covering Caterpillar, Cummins, Detroit Diesel, Navistar, Ford, Dodge, Volvo, Mercedes, and Paccar engine platforms.

The core product line is built on elastomeric sealing technology — O-rings, D-rings, X-rings, oil seals, valve stem seals, water grommets, and liner seals — produced with premium-grade material compounds including Viton, Aflas, HNBR, PTFE coatings, and silicone. Gasket sets span fiber/rubber with elastomeric beading, stainless steel with raised embossed beads, multi-layer steel, and edge-molded rubber variants. The portfolio extends to high-performance fasteners (8740 chromoly through Incoloy A-286), wire harnesses for Cummins and Caterpillar engines, replacement seal kits for diesel injectors, and engineered products supported by CAD-based design and reverse engineering. O-ring formulations are credited to a former Parker chemist and produced under a 30+ year partnership with a global O-ring manufacturing leader.

The business model is sales-led and transaction-based, with revenue generated from one-time sales of seals, gaskets, kits, fasteners, and wire harnesses, supplemented by Build-to-Order customization and private labeling services that let distributors and rebuilders apply their own branding. Pricing is not publicly disclosed and is confirmed at shipping due to ongoing tariff exposure. In December 2022, the company divested its Diesel Fuel Injector Seal Kit business to Drexel International and reinvested in its diesel engine parts and custom gasket set lines, opening a satellite Service and Technology office in June 2023 and adding C13 Gasket Sets and Piston Packs in February 2023.

Name

Magnum Diesel Parts

Legal name

Magnum Diesel Parts, Inc.

Website

https://magnumdieselparts.com

Company type

Private

Founded year

2003

Operating status

Operating

Headcount range

11–50 employees

Short description

Privately held Riverside, California-based B2B supplier of elastomeric seals, gasket sets, high-performance fasteners, and custom engineered components for the heavy-duty diesel aftermarket, serving engine rebuilders, distributors, and repair shops across construction, mining, marine, oil field, and trucking applications.

Ownership category

akta.pro rank

Product category

Heavy-Duty Diesel Aftermarket Parts (Sealing Products)

NAICS

Gasket, Packing, and Sealing Device Manufacturing (339991)

SIC

Gaskets, Packg & Sealg Devices & Rubber & Plastics Hose (3050)

akta.pro primary industry

Automotive Weatherseals, Gaskets & Sealing Systems Manufacturing (Door/Window/Trunk Seals) (IMACAKAI)

Keywords

• Diesel engine parts
• Heavy-duty gaskets
• Aftermarket sealing products
• O-rings and seals
• Engine rebuild supplies

Headquarters

HQ city

Riverside

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Operations, Personnel, Technology or R&D, Marketing or Sales

Revenue model

1. Gasket Sets & Seals Sales: Primary revenue from selling premium quality gasket sets, O-rings, D-rings, X-rings, oil seals, valve stem seals, water grommets, liner seals, and custom molded shapes for diesel engine applications. Products are sold to the heavy-duty diesel aftermarket including construction, mining, marine, oil field, over the road and stationary engine markets.

Go-to-market motion2 records

Distribution channels2 records

Marketing channels4 records

Core offering

Magnum Diesel Parts manufactures and supplies sealing products for heavy-duty diesel engines in the aftermarket rebuild channel, including O-rings, gaskets, gasket sets, seal kits, hardware (fasteners), and wire harnesses, with a specialization in Caterpillar engine gasket kits. The company sells directly to engine rebuilders, parts distributors, and repair shops, and supports those customers with Build-to-Order (BTO) manufacturing, private labeling, and custom engineering and product development services.

Product overview

Magnum Diesel Parts offers a comprehensive portfolio of sealing and engine component products for the heavy-duty diesel aftermarket. The core offering consists of O-Rings, Seals & Gaskets (including specialized elastomeric seals like Viton, Aflas, HNBR compounds), Gasket Sets for multiple engine brands (Caterpillar, Cummins, Paccar), and Hardware (high-performance fasteners). These are complemented by Engineered Products (custom development, CAD design, reverse engineering) and specialized Seal Kits for diesel injectors. The company also offers Wire Harnesses for Cummins and Caterpillar applications, Build-to-Order (BTO) customization services, and Private Labeling options. The portfolio is rounded out by Caterpillar-specific Engine Gasket Kits designed to cover wider serial number ranges than competitors.

Differentiator

Problem solved

Functional benefit

Brands

• BTO by MDP: Build-to-Order service offering allowing customers to customize products with their own branding

Products and services

• O-rings and seals O-rings and sealing components for heavy-duty diesel engine rebuild applications, supplied to engine rebuilders, parts distributors, and repair shops.
• Engine gasket sets (including Caterpillar engine gasket kits) Pre-assembled gasket sets that consolidate the gaskets and seals required for a diesel engine rebuild into a single kit, including specialty coverage for Caterpillar engines.
• Hardware (fasteners) Fasteners and related hardware components that complement the company's gasket and sealing products for heavy-duty diesel engine rebuilds.
• Wire harnesses Wiring harnesses supplied for heavy-duty diesel engine rebuild and repair applications.
• Seal kits Application-specific seal kits that group together the seals required for a particular heavy-duty diesel engine rebuild job.
• Build-to-Order (BTO) custom manufacturing Custom manufacturing service that lets customers specify the contents and configuration of sealing kits and related products, sold to engine rebuilders and parts distributors.
• Private labeling Service that supplies the company's sealing products under the customer's own brand, targeted at rebuilders and distributors that want to sell under their own label.
• Custom engineering and product development Engineering and product development service that works with customers on custom sealing solutions for heavy-duty diesel engine applications.

Quantifiable outcome

• Zero field failures in over 21 years of diesel service
• +2 more outcomes

Segments3 records

Ideal customer profiles1 record

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Two partnerships are on record, tiered minor and core.

• Drexel InternationalminorOthers · 1 December 2022In December 2022, Magnum Diesel Parts sold their Diesel Fuel Injector Seal Kit business to Drexel International. This divestiture allowed Magnum to re-invest in equipment and inventory to better serve their Diesel Engine Part and Custom Gasket Set customers. Drexel International is a Global Industry Leader in the re-manufacture and parts sales for Diesel Fuel Injectors.
• Global O-Ring Manufacturing PartnercoreOEM/ Whitelabel/ Licensing PartnerFor more than 30 years, Magnum Diesel Parts has partnered with a global leader in quality O-ring production. The company describes the relationship as being 'like family.' This partnership ensures seamless production with the highest quality criteria. The partner's commitment to excellence aligns with Magnum's high standards, enabling delivery of best-in-class O-Rings and Seals at competitive value.

Scale indicators5 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• MAHLE: Global automotive parts manufacturer with strong engine components and gaskets/sealing product lines, including heavy-duty diesel coverage. Comparable in aftermarket gaskets and seal kits but as part of a much wider portfolio including filtration and pistons.
• Parker Hannifin: Diversified industrial conglomerate with a major sealing technologies division. Not a pure-play gasket/O-ring specialist and far broader in scope, but directly comparable in elastomer sealing expertise and a recognized reference for Magnum's own chemist's background.
• Dana Incorporated: Tier-1 supplier of drivetrain, sealing, and thermal-management products for vehicle and heavy-duty markets. Comparable in aftermarket component supply and gasketing, but operates at scale across a broader product portfolio than Magnum.

Direct peers

• Garlock (EnPro Industries): Manufacturer of gaskets, sealing products, and fluid handling products for industrial and engine applications. Directly comparable in elastomeric and fiber-based gasket manufacturing for heavy-duty and industrial sealing environments.
• Corteco (Freudenberg Group): Aftermarket-focused sealing and vibration control brand of Freudenberg, offering gaskets, O-rings, and seal kits for engine and drivetrain applications. Directly competes in the same diesel and industrial engine aftermarket channels as Magnum.
• Freudenberg Sealing Technologies: Global manufacturer of sealing technology for automotive, heavy-duty, and industrial applications, with deep expertise in elastomer science. Directly comparable in O-ring, seal, and engineered gasket solutions and at substantially greater scale.
• ElringKlinger: German-headquartered manufacturer of gaskets, sealing technology, and engine components serving OEMs and the aftermarket globally. Directly comparable in product range (gaskets, elastomer seals, high-performance materials) and serves overlapping heavy-duty diesel applications.
• Fel-Pro (Federal-Mogul / DRiV): Fel-Pro is one of the most recognized aftermarket gasket and sealing brands in North America, directly competing with Magnum in engine gasket sets and seal kits for ICE and diesel engines. It is the most well-known direct competitor in the same heavy-duty diesel aftermarket channel.
• Trelleborg Sealing Solutions: Global leader in polymer sealing solutions including O-rings, rotary seals, and engineered elastomer products for automotive, heavy-duty, and industrial markets. Direct competitor in elastomeric sealing technology for demanding environments.

Regional players

• Drexel International: Mexico-based remanufacturer and parts distributor for diesel fuel injectors that acquired Magnum's injector seal kit business in 2022. Operates in the same diesel aftermarket, with a regional Latin American focus and complementary injector product set.

Market position

Strengths4 records

Weaknesses5 records

Competitive moat3 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/magnum-diesel-parts-inc

Revenue estimate

Valuation estimate

Number of profiles

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 Magnum Diesel Parts