​​Authorized Dealer

1 (800) 300-3697

John Unterseher

Our Mission Statement

It is imperative that every customer who chooses our company leaves satisfied and happy with the service we provided for them. At Central Diesel Sales,
it is our mission to serve our customers, community and region by providing the best professional, fast, friendly service possible.

                                                                      Furthermore, it is our mission to provide our customers with highest quality truck parts at a fair price and                                                                      to conduct our daily business practice ​with the utmost honesty and excellence.

About The Company

Our History

Over A Half Century In Business  -  Since 1962

Ron Unterseher, the founder of Central Diesel, grew up on a farm near Isabel, SD.  As a child, he spent a lot of time around trucks, tractors and all types of engines.  Ron's father, Dave, started Unterseher Trucking in the early 1940's and put his son behind the wheel of a straight truck at the age of 12.  Ron was hauling regularly for his father in the summer months at the age of 14.  A natural mechanic, Ron could fix almost anything as a teenager and young adult and had strong mechanical aptitude.  This led him to want to go to diesel school and learn all he could about the interworkings of diesel engines.  After attending diesel school in St. Louis and the Cummins Diesel training school in Indiana, Ron came home to South Dakota and built his own diesel shop on the east side of Mobridge in 1962.  

Central Diesel Sales was started partly to support and maintain Dave Unterseher's fleet of trucks and trailers and to provide service and parts to area trucking companies, farmers and ranchers.  As the company grew, Ron added Cummins, International Harvester and Caterpiller diesel engines as dealerships and sold farm trucks, International Scouts and Pickups, school buses, medium and heavy duty trucks and irrigation engines around the area.  In 1970, Dave sold out of his trucking company and retired and in 1974, Ron decided to add on to the original shop and build a large parts area.  Over the years, the business grew and times changed. Other businesses grew up around it and soon neighbors included a trucking company, a beer distributor, a farm equipment manufacturer and an auto repair business. By this time International Harvestor changed to Navistar International.

In 1995, the shop space at CDSI was enlarged and additional bays were added to increase the work space and productivity even more.  In 2015, a Tire Shop was added that caters only to semi truck and trailers. Today, Central Diesel has 10 service bays to accomodate the needs of our area customers and over the road truckers.

Today, we continue to enjoy our 54 year dealer relationship with Cummins, as well as our long standing TEPS relationship with Caterpiller and work on all makes of diesel engines including International, Detroit Diesel, Mack and Mercedes as well.  In March, 2013 we became an Authorized Distributor for Delco Remy Products.  We are carrying a large inventory of starters, alternators and motors for all automotive and diesel applications for our customers in north central South Dakota.

The continued longevity of Central Diesel and it's success has much to do with the business philosophy and the sense of fairness that both Dave and Ron Unterseher put into their businesses.  Always treating customers with respect and providing the best service possible. The Unterseher family has a long history in the Mobridge area and has been in business for a combined total of over 120 years, over 80 of those years in the trucking industry.

In 2011, Ron handed the day to day operations over to his son, and in 2014, sold the business to his son John                                                                                                                                  Now the owner of Central Diesel Sales, John Unterseher will continue on the traditions started by his grandfather and his father                                                                                     and take the business into the future as diesel technology and the trucking industry changes and grows.  Central Diesel is 55 years                                                                                  old this year.  We look forward to 55 more years as the areas leader in diesel parts and service.