Circle D Transmission of Houston, Texas was founded by Dennis and Patricia Sehorn on June 6th, 1976. From its inception, the company has successfully navigated the winds of change. For over 43 years, Circle D has evolved into the great company it is today by proactively responding to change-driven challenges – some good and some absolutely devastating. 
Over the years, Patricia has observed, “You can’t stop change, so when change dictates, embrace change.” To help you fully appreciate the courage of Patricia’s statement, you need to know the full extent and depth behind it. You see, she isn’t just saying it, she’s living it. In 2004 Dennis and Patricia received disastrous news; Dennis was diagnosed with Amyotrophic Lateral Sclerosis (ALS), commonly known as Lou Gehrig’s Disease. After a valiant 4-year battle, Dennis passed away from this devastating illness. Using Dennis’s death as a baseline, I think you can see why Patricia can embrace whatever else life has to offer – good or bad. Out of the tragedy of losing Dennis, his family started The Dennis Sehorn Foundation. Money raised goes to help people living with ALS to pay for out-of-pocket, caregiver and medical expenses.
The Evolution of Circle D Transmission
One fateful day back in the early ’70s, Dennis stopped by a friend’s transmission shop to make a call about a shop he’d seen for lease. He wanted to open a paint and body facility. His friend overheard the conversation and, being shorthanded at the time, offered him a job in his transmission shop. Dennis accepted the position on a temporary basis.
However, Dennis became intrigued with transmission repair, and before long, he was running the shop. New hope of a bright future in the transmission industry ignited the fire of his entrepreneurial dream of shop ownership.
In 1976, Dennis and Patricia decided to take a leap of faith by renting a small two bay shop, and they opened for business as Circle D Transmission. If you’re wondering where the name came from, Dennis was also heavily involved in Sprint Car Racing – “Circle” represents the circular track, and “D” is for Dennis.
Things were quickly going well, and the business was growing. While owning and operating the growing company, they also found time to raise 2 children, Chris and Sherry.
Eventually, in the early ’80s, Dennis and Patricia decided to buy their own land and to build a shop. However, having established a good customer base, they wanted to remain in the same area. Their dream of owning their building and land became a reality with a facility featuring 4 lifts and 2 rebuilding stations.
That building worked well for many years, but as they continued to grow, they needed more space. So, in the early ’90s, they expanded by acquiring the building next door. Today, Circle D has 9 lifts in the shop area and 5 rebuilding stations in a climate-controlled building room. They also have a comprehensive arsenal of scanners and computers for late model automobiles – on par with those found in the dealerships.
We all know that the best transmission is only as good as the torque converter. That fact wasn’t lost on Dennis. To control quality, they started rebuilding torque converters in the early ’80s, primarily for their own use, but eventually for resale to other shops. Today, the torque converter operation does business under the name, Circle D Specialties, and it’s owned by their son, Chris Sehorn and his wife, Ann. They specialize in performance torque converters.
The Backbone of Circle D
Dennis and Patricia knew that developing their own technicians would yield the cream of the crop. Their business model was to train and promote from within. You need to look no further than Circle D’s current team for proof that their concept works.
For instance, Circle D’s lead transmission technician and diagnostician, David Dolejsi, worked his way up the ladder. He began as a 17-year-old sweeping the floors after school while still in high school. This year he celebrated 34 years at Circle D. David’s attention to detail is a major contributor to Circle D’s outstanding reputation for quality.
Similarly, Glenn Riske began in the R&R department, moved to the building room and now serves as their service advisor. Glenn just celebrated his 30th anniversary at Circle D, and his outstanding people skills combined with his integrity, has helped shape Circle D into what it is today.
Lead chassis technician, Ron Goodwin, has been with the team for over 18 years, and shop porter, Carlos Martinez, has been with them for over 23 years. Both Ron and Carlos have, through their dedication and team commitment, played an integral part in Circle D’s success.
Circle D continues the development of young blood with its latest hire, Corey Fitzgerald. Cory is 19 years old and has already been with the company for 2 years as a trainee.
Sherry Sehorn Dolejsi began doing office work for the family business in the early ’90s while she was attending the University of Houston. After graduating with a degree in Marketing in 1997, she decided to make Circle D her career. Today, she and her husband, David Dolejsi, are partners in the company, along with her mother, Patricia.
What’s Next?
It should come as no surprise that in the spirit of embracing the winds of change, the evolution of Circle D continues. In recognition of the rapidly expanding demand for high-performance transmissions and high-performance transmission parts, the company is carving out a niche position in this worldwide market.
Circle D is already entrenched in the development, design, manufacturing, and distribution of performance parts for GM and Ford 6-speed automatic transmissions. They’re in the R&D phase for the 8-speed and 10-speed transmissions as well. Unlike most competing products, their performance parts kits come with detailed, step-by-step instructions, specs, and pictures.
The relationships that Circle D has developed with the large aftermarket transmission component manufacturers have made these performance advancements possible. The company also utilizes several high-performance vehicles including their own Gen 5 Camaro for R&D.
Circle D currently rebuilds and ships performance transmissions on a custom, one-off basis worldwide. They plan to stock units soon. They ship transmissions and parts kits within the US and internationally.
At the present time, 25% of their overall business is from the performance market, but they look to quickly increase that percentage to 50%. Sherry commented, “The internet has made the world just as easy to reach with our marketing message as it is to reach the local market.”
Circle D Hasn’t Forgotten Its Roots
The company’s commitment to providing its Houston customer base with its acclaimed, quality transmission service remains intact. David commented, “We look out for our customers’ best interest. We stick with what we do best and know there are times that a reman is the best choice.” He added, “Making the right repair begins with an accurate diagnosis. We’re heavy on diagnostics with OE scanners for Ford, Chrysler, and GM. We also feature flash and enhanced calibration capability with HP Tuners and EFI Live.”
Patricia summed it up with this bottom-line statement, “We offer a friendly, welcoming atmosphere, and live by the Golden Rule. That’s something that will never change.”
