In 1960, Eldon married the love of his life, Pat. After completing his degree, he began his lifelong dream career at Caterpillar Inc. in 1963. Eldon loved his work, so much so that colleagues often joked he had “yellow blood.” A practical man and a gifted problem solver, Eldon spent nearly 40 years at Caterpillar, working in a variety of engineering and research roles.
He was instrumental in the first design of the D10, one of the highlights of his career. As part of the D10’s 40th anniversary, Eldon was interviewed by Caterpillar and he and Pat attended the celebration along with others involved in the project. His work on the D10 resulted in many of his 14 patents issued over his career. Eldon later worked on missile launcher designs for the U.S. government within Caterpillar’s defense products division, and he eventually concluded his career in the Research Department, contributing to future vehicle design. Upon his retirement in 2002, he was honored with a plaque recognizing his innovative contributions and his mentorship that inspired thousands of ideas throughout his leadership years.
Eldon was a man of faith and an active church member throughout his life. He belonged to Advent Lutheran Church and later Bethel Lutheran Church in Morton, Illinois, where he served on the church council, as Sunday School Superintendent, and on the calling committee. After moving to Lincoln, Nebraska, he and Pat became members of Messiah Lutheran Church.
Outside of work, Eldon embraced nature and loved spending time outdoors. He enjoyed many years of fishing trips to Canada with close friends. He also loved hunting, woodworking, and working on anything with his hands. He and his son, Mark, completed many projects together, including rebuilding a dune buggy. He also spent many hours in the garage with his friend, Randy, where they worked together to rebuild a car. As a father, he coached little league; as a grandfather, he volunteered at the Bethel Lutheran School library and drove students to and from school activities.
Eldon will be remembered for his quick wit, his warm humor, and his love of dancing with Pat even recently, enjoying dances together in the kitchen. After retirement, he and Pat spent winters in Florida, where Eldon set up a small workshop in the garage to help friends and neighbors fix things.
In 2019, Eldon and Pat moved to Lincoln, Nebraska. After years of health challenges, Eldon was later diagnosed with Lewy body dementia with Parkinson’s. He resided at The Knolls Senior Living during his final year and passed peacefully, surrounded by loved ones, as he entered the kingdom of God.
Eldon is survived by his devoted wife, Pat; his children, Rhonda Oestmann and Mark Oestmann, together with Mark’s fiancée, Debby Martinko; and his grandchildren and great-grandchildren: Candace and Ian Stoeckley; Heather, Jarrett, Kale, and Aiden Newman; Barret, Abby, and Connor Storck; Travis Oestmann and Meredith Brown; and Jessica and Jake Nimesgern. He is also survived by his brother, Ralph Oestmann, and his wife, Donna, as well as their children and grandchildren. He was preceded in death by his parents, Ervin and Edna Oestmann.
Eldon’s legacy lives on through the family he loved, the friendships he cherished, and the countless innovations and ideas he brought into the world.
Funeral Service to be held 1:00 p.m., Monday, December 1, 2025, at Messiah Lutheran Church, 1800 S. 84th St., Lincoln, NE 68506. Visitation 1 hr. prior to the service.
Memorials may be given to Messiah Lutheran Church or Dementia Society of America (Lewy Body Research), Post Office Box 600, Doylestown, PA 18901 USA