John’s life started in Detroit, Michigan, in 1940. He attended Catholic school at St. Bernard’s and St. Joes while being raised in Harper Woods. John went to Wayne State University while supporting his new family and earned a degree in political science. His degree would lead him to service in the federal government, helping veterans with claims at the Department of Veterans Affairs for 38 years.
John was a master of trivia, so much so that he was rarely invited into Trivial Pursuit games with his ability to recall obscure events or people in sports like the 1965 Detroit Tigers roster or the origins of the Bobby Layne curse that never released its grip on the Lions. He could tell grand stories in the traditions he learned from his Irish family. He was also an enthusiastic book reader.
He would consider himself a lucky man, a happy Irishman that would, in his terms, observe that an Irishman has an abiding sense of tragedy to get him through the fleeting moments of happiness. John would have the fortune of romancing two wonderful women and continuing the relationship until death parted them.
John McMahon is survived by his wife, Patricia (Trish) McMahon. He was married to Joan McMahon (Sturtecky) with whom he raised three children. He is survived by son John McMahon, Jr., his wife, Susan, and their children, Marina and Olivia. Daughter, Julie Jensen, and spouse Jeff, and their children, Lauren and Chelsea. He was preceded in death by his son, Joseph (JP) McMahon, his surviving spouse Nancy, and their children, Mara Ogarevic, spouse Voja, and their daughter Mila, Megan and Joey. He is also survived by his step-children, Daniel Cachia and spouse Jill, and their children, Sydney and Daniel, Cindy Lawson and her spouse Lance, and their daughter, Lily. John is also survived by his brother Patrick McMahon.
The family is honoring John’s wish to choose cremation. A memorial mass will be held on June 20, 2026, at 11:00 a.m. in St. Colette’s Roman Catholic Church, located at 17600 Newburgh Road, Livonia, MI 48152. He will lie in state at 10:30 a.m. A luncheon will follow the ceremony.
The family requests donations to the following charities in lieu of flowers:
Gleaners Community Food Bank:
https://donor.gcfb.org/page/donate
Guitars for Veterans:
https://guitars4vets.org/?form=g4v-home
American Heart Association:
https://www.heart.org/en/get-involved/ways-to-give
University of Michigan Alzheimer's Disease Research Fund:
https://giving.umich.edu/basket/fund/307386
