Northern Illinois Mack, Inc.

Established 1973 - 847-223-6666

About Us

In 1960, Steffenhagen Equipment was founded in Grayslake, Illinois by Bill and Ann Steffenhagen.  This family run business was founded to meet an overwhelming need for a truck repair facility in northern Illinois.  Even from the beginning, the values of customer service, hard work, innovation, loyalty, and fiscal responsibility guided this corporation.

Due to their success, Steffenhagen Equipment was able to expand and in 1973 became a full Mack dealership.  Another location was added at that time, in Rockford, Illinois and the corporate name was changed to Northern Illinois Mack Incorporated.

Continuing to build on their guiding principles of hard work and customer service, a third location was added in 1991 in Mendota, Illinois.  Within a few years, a new facility was constructed in LaSalle, Illinois.  The Mendota location was moved to LaSalle, where it still remains today. Contact us at 847-223-6666

In 2002, the company expanded once again to include Rockford Truck Sales & Services, Inc.  The existing Rockford store was moved to a new facility in Loves Park, Illinois.  This strategic move added the Kenworth, Volvo, and Isuzu product lines to the company. 

Over the course of the years, Ann and Bill’s children, in-laws, and grandchildren became a part of the business and continue to contribute to its growth and success!

Today, the company has over 125 employees between the three locations.  Many of the employees have over 30 years of service to the company and are certified in their areas of expertise.  The principles of customer service, hard work, and innovation that helped to create and build this company are still a guiding force in the daily operations of this business.  We are proud to still offer a variety of specialized services with excellent customer service!