What The Diez Group makes

The Diez Group is a Dearborn, Michigan steel and aluminum processor: it takes flat-rolled coil from the mills and turns it into the blanks, welded blanks, and slit coil that feed automotive stamping lines. The core services are precision level blanking, scallop blanking, precision slitting, cut-to-length, laser welding, milling, washing and oiling, and climate-controlled warehousing with just-in-time logistics. The group works in both steel and aluminum, and it sits at the front end of the supplier chain, one step upstream of the OEMs and Tier 1 stampers it supplies.

Laser welding is a distinct capability here, not a line item. In 2010, the group's foundational company, Delaco Steel, formed Delaco AMTB with ArcelorMittal Tailored Blanks Americas, a 51/49 minority-owned joint venture running laser-welding plants in Dearborn and Tonawanda, New York, to make laser-welded blanks for the automotive industry. Laser-welded blanks combine different steel grades or thicknesses into a single blank before it is stamped, which lets an automaker put strength where a part needs it and save weight everywhere else. The company reports investing more than $14 million in machinery upgrades over a recent three-year period.

Scale and footprint

The Diez Group describes itself as a conglomerate of eight companies spanning roughly 2 million square feet across 10 facilities in six states. A 2026 profile of the company put its headcount at about 475 employees and its revenue at $1.1 billion. Named operating locations include the Dearborn headquarters and Delaco Steel plant, a Woodhaven, Michigan processing plant, the Tonawanda, New York laser-welding plant, and processing and logistics sites in Jeffersonville, Indiana; Kansas City, Missouri; and Montezuma, Iowa. The Dearborn plant runs large blanking presses and racked coil storage for steel and aluminum, the machinery a service center needs to deliver blanks and slit coil on a stamping plant's schedule.

Ownership and history

Gerald Diez Sr. and Brenda Diez founded Delaco Steel in 1973. The business grew into an anchor Hispanic-owned supplier in the Detroit automotive base, and it is both a certified Hispanic minority business enterprise and a WBENC-certified women-owned business. April Diez became chief executive in 2022, after the death of her father; she had joined the company full time in 1985, worked through shipping, inventory control, costing, and purchasing, and served as chief operating officer for 25 years before taking over. Her brother, Jerry Diez Jr., is president, and the two run the group together. The company keeps family, faith, and community at the center of how it describes itself, and third-generation family members are now active in the business.

Certifications and quality

The Diez Group states that it is IATF 16949 and ISO 14001 certified, the automotive quality-management and environmental-management standards expected of a direct-material supplier to the OEMs. Its quality record with Ford runs deep: in 1997 Delaco Steel became the first minority steel service center to earn Ford's Q1 supplier quality award, and in the early 1990s the company helped launch Ford's Raw Material Supply Program. Because it supplies blanks and welded blanks directly into stamping and body-in-white operations, the group's work is governed by the same production part approval discipline its automotive customers require.

Known customers

Ford is the anchor. The other automaker relationships are reported through a major-outlet profile rather than documented through filings, so they are marked accordingly.

Beyond Ford, the customer list is not individually published, which is normal for a steel service center serving OEM and Tier 1 stamping programs. Buyers weighing a domestic, nearshoring-friendly source for blanks and welded blanks will find a supplier whose entire footprint sits in the US industrial Midwest.

Frequently asked questions

What does The Diez Group make?

The Diez Group is a steel and aluminum processor. It supplies precision blanks, laser-welded (tailor-welded) blanks, slit coil, and cut-to-length material to automotive stamping and body-in-white operations, along with milling, washing and oiling, warehousing, and logistics. Its foundational company is Delaco Steel Corporation in Dearborn, Michigan.

Who owns The Diez Group?

The Diez Group is a private, family-owned business, founded by Gerald and Brenda Diez in 1973. April Diez is the chief executive officer, and her brother Jerry Diez Jr. is president. It is a certified Hispanic minority business enterprise and a WBENC-certified women-owned business.

How big is The Diez Group?

A 2026 profile reported about 475 employees and $1.1 billion in revenue. The group describes itself as a conglomerate of eight companies spanning roughly 2 million square feet across 10 facilities in six states.

Where is The Diez Group located?

Its headquarters and flagship Delaco Steel plant are at 8111 Tireman Ave, Dearborn, Michigan 48126. It operates additional plants and logistics sites in Woodhaven, Michigan; Tonawanda, New York; Jeffersonville, Indiana; Kansas City, Missouri; and Montezuma, Iowa.

Who are The Diez Group's customers?

Ford is the documented anchor customer, a relationship dating to the late 1970s that includes Ford's Q1 award (1997) and a 2015 Ford World Excellence Award. Reported customer recognition also comes from General Motors, Stellantis (Fiat Chrysler), and Johnson Controls. Most customer names are not individually published.

What certifications does The Diez Group hold?

The company states that it is IATF 16949 and ISO 14001 certified. It was the first minority steel service center to earn Ford's Q1 supplier quality award, in 1997.

Last verified September 28, 2026. Is this your company? Request a correction.