John “Jack” C. Sullivan, 90, of Oshkosh, embarked on his final journey surrounded by love at Aurora Medical Center on May 20, 2026. Born on December 4, 1935, to the late Humphrey and Beatrice (Mullarkey) Sullivan, Jack lived a life filled with adventure, laughter, and cherished moments with family and friends.

In 1963, Jack was united in marriage to Marilyn Egan, and together they raised four children. Jack proudly served his country in the United States Army from 1955 to 1957, earning an honorable discharge that reflected his dedication and service. He spent his career as a long-haul truck driver, affectionately earning the nickname “Bumper Jack” for his expert navigation of the highways across the nation.

Jack was known for his joyful spirit, relishing time spent with his breakfast and lunch groups. His passions included snowmobiling, NASCAR, meticulously tending to his yard, and keeping his grass perfectly mowed. A devoted sports fan, he would often be found cheering on the Brewers, Badgers, and Packers, and indulging in his favorite soap operas.

He is survived by four children, Julie (Rick) Kelly, Kelly Sullivan (Eric Kolb), Edward Sullivan (Paula O'Donnell), Mark Sullivan; grandchildren, Erin (Karl) Kraebber, Corey (Kelsea) Ansfield, Megan Kelly, Kristen (David) Paulsen, Spenser Sullivan, Garrett Sullivan, Ireland Sullivan, Grady Sullivan (Alexis Pfeilstifter), Kaylin Werth; great-grandchildren, Allyson and Hadley Kraebber, Reese Ansfield, Levi and Landen Werth; siblings, Mary Grace Langenfeld, Tom (Sue) Sullivan; in-laws, Nan (Andy) Amend, Ken Pryne, Greg Kroll. He had a special place in his heart for all his nieces and nephews, and is further survived by many other relatives, and friends.

In addition to his parents, Jack was preceded in death by his wife, Marilyn; siblings, James (Joyce) Sullivan, Ann (Ron) Korb; in-laws, Ralph Draeger, Ed Langenfeld, Bernice Pryne, Doris Kroll, David Egan, Richard (Ann) Egan; special nephew, Patrick Sullivan.

A Mass of Christian Burial will be held at 11:00 a.m. on Friday, May 29, 2026, at St. Raphael the Archangel Catholic Church, 830 S Westhaven Dr, Oshkosh, WI 54904. Visitation will be held at the church from 9:00 a.m. until the time of the service. Burial with Military Honors will be held immediately following the service at Sacred Heart Cemetery.

In lieu of flowers, a memorial will be established in Jack’s honor. The family extends heartfelt gratitude to the Two Brothers crew for embracing Jack as family and bringing joy to his life.

Rest in peace Bumper Jack.