John Frank Nemechek (March 12, 1970 – March 21, 1997) was an American racing driver who competed in the NASCAR Craftsman Truck Series.

The younger brother of four-time NASCAR Cup Series race winner Joe Nemechek, John followed his brother into racing, participating in his first race at the age of twelve in an 80 class dirtbike race. After a quick progression to the 250cc class, he moved onto mini-stock cars, where he raced against his brother, and eventually late-model stocks.

When he was not racing, Nemechek served as the front-tire changer on Joe's pit crew, and was on Joe's 1992 NASCAR Busch Series championship-winning team. He would begin attempting NASCAR races himself, and ran one Busch race at IRP in 1994.^[1] He finished 30th after his No. 89 Chevrolet suffered an engine failure. The following season, he began racing in the new Craftsman Truck Series, driving at first for Redding Motorsports,^[2] and then for his brother's NEMCO Motorsports. In the first year of competition, Nemechek ran 16 races and had two top-ten finishes. He followed that up with two more top-tens in 1996 and a thirteenth-place finish in points, running a single truck he built himself titled the War Wagon under his own team, Chek Racing.

On March 16, 1997, Nemechek was running a Truck Series race at Homestead-Miami Speedway when with 14 laps to go, he lost control and struck the first-turn wall, driver's side first, and hit his head on the wall, suffering head injuries. He was extracted and transported to a hospital, where he died on March 21, 1997.^{[citation needed]}

Following the incident, Homestead was reconfigured into a true oval with a six-degree banking to reduce the possibility of the type of crash that killed Nemechek. His brother Joe won a Busch Series race that November at the reconfigured circuit; he later named his son John Hunter after his late brother.

In 1999, when Joe won his first Cup Race at New Hampshire, he paid tribute to John over the radio while he took the checkered flag:

“This is for my brother John. I love you.”^[3][4]