Great question — answering as the UphillTech team:
My hubby was a diesel mechanic for years. All I had to do was wash his clothes in Tide to remove the smell. However, since using detergent hasn't worked for you, try what a friend of ours had to do. He had to soak his clothing in vinegar, completely immersing, letting them dry and then washing. Hope this helps.
Full answer by Jane Westin: https://lifehacks.stackexchange.com/a/4043 (CC BY-SA 3.0).
Need it done for your business? UphillTech.