Truck nuts, also called truck nutz, are plastic or metal accessories for pickup trucks (and other vehicles) which resemble a pair of dangling testicles. They are attached under the rear bumper or trailer hitch of the vehicle so they are visible from behind.
The truck nuts phenomenon existed in small numbers in custom-made form beginning in the 1980s. The earliest known commercial store-bought truck nuts appeared in the late 1990s but remained a limited phenomenon. However sometime in the mid to late 2000s, Truck Nuts exploded, becoming well known throughout society even featuring on national television shows.
A number of people claim to have invented the truck nuts industry (ie. plastic store-bought truck nuts). David Ham (alias Bozzy Willis), owner of YourNutz.com, said he saw a pair of custom nuts at a rally in the 1980s, then in 1996 began manufacturing and selling plastic nuts commercially. John D. Sallers, owner of BullsBalls.com, says he was out 4x4'ing when someone yelled "Go Ernie, show'em you got balls!" and with that he came up with the idea and began selling them in 1999. The two men sold Truck Nuts through the late 90s and 2000s, competing both in the market and in private exchanging angry phone calls and emails. This conflict escalated into PR wars, social media conflicts, posts on review sites, blog attack posts and finally leading to legal cease and desist orders.  Vice News called it the 'Great Truck Nuts War'.
In 2007, a proposal was made by Maryland politician LeRoy E. Myers Jr. in order to prohibit motorists from "displaying anything resembling or depicting 'anatomically correct' or 'less than completely and opaquely covered' human or animal genitals, human buttocks or female breasts". He referred to the testicles as "vulgar and immoral," and stated that his proposal was made at the request of a resident who was offended by the accessory. On January 15, 2008, Virginia Delegate Lionell Spruill proposed Bill HB 1452, which would prohibit truck owners from displaying or otherwise equipping their vehicles with devices resembling human genitalia. In April 2008, Florida lawmakers launched an additional attempt to ban truck nuts, making their display punishable by a $60 fine.
In 2011, a 65-year-old South Carolina woman was ticketed by the town's police chief for obscenity for adorning her pickup truck with truck nuts. The case, originating in Bonneau, S.C. (population approximately 480), was pending jury trial on her $445 traffic ticket. As of July 2012, her case had been continued three times and had no new trial date set. According to the Above the Law legal analysis blog, the ban was discussed in the ABA Journal and presented constitutional freedom of speech questions. The stated position of the Honolulu Police Department in 2013 from their city corporation counsel's office concerning obscene bumper stickers is, "It may be tasteless but it's protected as free speech." This is because it does not violate the First Amendment, nor is it specifically stated as against the law.
- Blair, Zachary, "Junk in the Trunk: A Queer Exploration of Truck Nutz as Contemporary Material Culture," paper presented at Queertopia, Northwestern University Graduate Student Conference, Chicago, IL, 2009.
- Rein, Lisa (February 23, 2007). "Fake Private Parts Are No Joke, Myers Says". Washington Post. Retrieved July 10, 2014.
- Mack Lamoureux (July 20, 2015). "Balls Out: The Weird Story of the Great Truck Nuts War". Vice News. Retrieved July 24, 2017.
- Delegate Lionell Spruill, Sr. (December 2008). "HB 1452 Display of offensive objects or devices; prohibited on any vehicle.". Virginia General Assembly Legislative Information System. Retrieved 4 December 2011.
- Lewis, Bob. "Watch what you put on trailer hitches". Associated Press – via HighBeam (subscription required).
- Peltier, Michael (2008-04-25). "State moves to ban fake testicles on vehicles". Reuters. Retrieved 2009-03-11.
- "Hanging of 'Truck Nuts' Grows into a Free Speech Debate". Fox News. August 2, 2011. Retrieved November 14, 2016.
- Dills, Todd (August 3, 2011). "‘Truck nuts’ in litigious fire in South Carolina". Overdrive Magazine. Retrieved November 14, 2016.
- McCue, Dan (August 3, 2011). "South Carolina Astir Over Giant Truck Nuts". Courthouse News Service.
- Munday, Dave (July 27, 2011). "Obscenity case will be heard by jury". The Post and Courier - Charleston, SC. Archived from the original on 2012-01-31. Retrieved February 14, 2012.
- Phillips, Tony (July 11, 2012). "Truck Nuts a No-No in South Carolina". The Huffington Post (blog). Retrieved November 14, 2016.
- Elie Mystal (July 28, 2011), "Is A Ban on ‘Truck Nuts’ Unconstitutional?", Above the Law (blog)
- Watanabe, June (September 18, 2013), "Offensive decor on vehicles counts as protected speech", Honolulu Star-Advertiser, Oahu Publications Inc. – via ProQuest (subscription required)