Jerry & Mary Ellen Heirigs

Jerry has always dreamed of owning his own repair shop since he graduated from Mitchell Vo-Tec. He spent several years working at a transmission shop and a dealership preparing him for the opening of J & M Transmission in August 1993. Jerry started J & M as the owner, builder and janitor. As the business grew and the automotive industry changed, J & M service expanded to include general repair and added several staff members. Today we have 6 employees and an 8400sq. foot air-conditioned shop. “We are a full service repair shop that fixes the whole vehicle not just the transmission.

We are committed to customer’s service! With that being said, not only do we shuttle customers but we also offer at no additional cost, free vehicle pick-up. So in other words, J & M will pick up your vehicle while you’re working, service it, and then return it back to your work or home all without you leaving your office chair.

After 20 years of nursing, Mary Ellen decided it was time to join the family business. In spring 2004, she started working with our customers and taking care of the marketing and advertising. When asked if she misses nursing she says “No! When customers call and the vehicle are broken down it’s a big problem. So whether it’s a phone call with a sore toe or a broken down vehicle, we need to help fix the problem.”

We have been married for over 36 years. Our youngest son, Jeremy graduated from Southeast Tech with a degree in Collision Repair and is working for ABRA North in Sioux Falls. Jeremy is restoring a 1966 Ford LTD 2 door hard top with his dad.

Service Advisor

Justin Ymker

Justin joined J & M Transmission in 2015 with over 12 years’ experience in automotive parts industry and 6 years in management. At J & M, Justin is now a Service Advisor helping out in the front office. Justin lives in Sioux Falls with his wife Kristel and enjoys woodworking and fishing. Justin and Kristel are parents to a little boy, Finn, who is a precious 3 year old keeping the parents running as well as his older sister Bella who likes to help out with Finn.

ASE Certified Master Technician with L1

Scott Nielsen

Scott comes to J & M transmission with 28 years of GM, Honda, and Ford dealership experience of which the last 15 years he was the service manager in South Texas. Scott is an ASE Certified Master technician and is originally from rural Viborg area. Scott moved back to South Dakota in spring 2011 with his wife, Helen and son Thomas. Their other son Christian and daughter Aubrey live in Texas. Scott enjoys hunting and fishing with his son. Scott is our outside technical support and salesman for our wholesale transmission sales.

Isaac Schorer

Isaac graduated with honors from Southeast Technical College. He and Katy are both originally from Fulda, Minnesota. Isaac moved to Sioux Falls to pursue his degree to become an Automotive Technician and Katy moved to Sioux Falls to pursue a bachelors degree in nursing at the University of South Dakota, she has recently graduated from USD with her degree in Nursing and is officially an RN!

Isaac and Katy have a two year old little boy named Hudson and a second child on the way. He is a very happy content little boy and we all love him! Katy has recently graduated from USD with her degree in Nursing and is officially an RN!

“I really enjoy working at J & M Transmission and Auto Service! Katy, Hudson and I would like to stay in the area after Katy graduates nursing school so that I can continue working here. Jerry and Mary Ellen have treated us both very well – we feel as though we are part of their family!”- Isaac

In his spare time, Isaac likes to hunt, fish, and go to tractor pulls with his family.


Kiron is an ASE Certified technician and.has been a technician since 1997. He is highly skilled in electrical diagnostic, among many other things. He loves the challenge that diagnosing broken vehicles presents and he is always searching for the “why” behind what’s going on with a car. He and his wife, Michele, live in Elk Point, SD and have 2 cats. They enjoy traveling to the Black Hills in their free time, and Kiron also enjoys woodworking and cooking!

Isaac Norton

YES, we do have two Isaacs working at J & M! Isaac Norton is a graduate of Aberdeen Roncalli Sr. High School, in Aberdeen, SD. He is also a graduate of Southeast Technical Institute in Automotive Technology. Isaac, or “Rami” as we affectionately call him, is recently engaged to Cacie and they are planning a wedding in early 2022. (Isaac #2)

Hunter Thomas

Hunter is a graduate of New Tech High in Sioux Falls and began his automotive career after graduating from Southeast Technical Institute. Hunter has been working at J & M for over a year and is a great part of our team. When he’s not working, Hunter enjoys hanging with friends and riding his motorcycle. Also, Hunter has a Goldendoodle named Lexi and enjoys vacationing in Cabo.

Customer Greeter


I am a Boston Terrier and Beagle mix and I am the official customer greeter! I love to chase leaves and bunnies when I am outside. When you come to J & M, you can play tug of war with me…..please!

Kati Franco

Kati is a skilled service advisor at J&M Transmission & Auto Service. She has been helping customers get the parts and services they need for their vehicles for 6 years. She is the smiling face that makes sure you’re taken care of!

Four years ago, Kati moved to South Dakota from California with her kids, Kyle, Eli, and Remi, and their dog, Oliver to make a better life for their family. They love our community! In her downtime, she enjoys spending time with her children and watching football.