About Us
Founded in 1958, Diesel Specialists of Green Bay Inc. has been locally owned and managed for over 60 years.
Locally Owned History
2001
Brian and Wendi Tomcheck purchased Diesel Specialists in 2001. Brian can repair anything diesel, but his area of expertise is rebuilding diesel engines and transmissions. After earning a degree in automotive repair from Northeast Wisconsin Technical College, Brian worked as a diesel technician in Central Wisconsin for 24 years before he and Wendi purchased the business.
2006
The Tomchecks moved Diesel Specialists to the newly built state-of-the art facility at 2264 Mid Valley Drive in De Pere, Wisconsin. With an eye on the future, the Tomchecks designed the service bays to accommodate all sizes and types of heavy-duty equipment.
2009
Brian & Wendi’s son Brad began working for the company as a Diesel Technician. Brad earned a degree in Diesel Technologies and Diesel Mechanics. As of 2025, Brad is the GM of Diesel Specialists and works every day to continue to the legacy that Brian and Wendi curated.


Diesel Engines
Our experienced and certified technicians utilize the latest technology to access information for each engine line to be able to accurately diagnose and successfully repair or rebuild a diesel engine.
Fuel Injection
We have a strong team of technicians that know all the inner-workings of mechanical and electronic controlled pumps, along with mechanical and common-rail injectors. In 2009, we were the first service dealer in North America for Common Rail Injectors. Whether you need partial repairs or complete rebuilds, we are happy to provide top-quality repairs.
Parts
Whether you need parts delivered or set outside for after hours pick-up, we can find a way to get what you need.
Testimonials
I’ve been working with these guys for over 10 years now, and I would bet my last dollar that you can trust Diesel Specialists Green Bay with your Engine. Genuine parts, fixed right the first time. When equipment down time is on the line, the team at DSGB gets you up and running promptly so you can get that machine back to revenue generating service.
Ron Schmidt
Diesel specialists repaired and reinstalled my injector pump on my skid steer. It runs well now with no leaks.
Kevin King
Best place to talk to for anything diesel related. They are outstanding people with great service and knowledge!
Jason Rumohr

