For years, NASCAR has used five lug nuts on a race car's wheels. At the conclusion of the 2020 season, that is set to change. NASCAR is planning to switch to a single lug nut for fastening tires during pit stops. The new procedure is expected to start at the beginning of the 2021 season.
The move to a single lug nut was brought on by new 18-inch aluminum wheels, which are three inches larger than the wheels that NASCAR currently uses.
"The answer became pretty clear that we needed to go single lug nut," NASCAR senior vice president of innovation John Probst said. "And I know that a lot of folks might say, 'Well, if product relevance is your main goal, name me a car that has a single lug nut.' I'm not sitting here saying I could, but I can name lots of cars that have 18-inch aluminum wheels. And that once we decided 18-inch aluminum wheels was the primary driver, the engineering solution was pretty clear."
Probst also revealed that the new wheels see their durability decreased by 30 percent if they're using five lug nuts.
"It's almost never the case that all five lug nuts are literally tight to the wheel, and if we don't have five lug nuts tight to the wheel, the durability of an aluminum wheel drops," Probst added. "If all lug nuts could be guaranteed tight, five is a workable solution. With the pressure to do a very fast pit stop, I can't say that we have knowledge that all five are ever completely 100 percent tight to the torque spec."
Probst also confirmed that the majority of teams are more than willing to move to the single lug nut method. It's also estimated that the single lug nut will take around 0.5 seconds to remove rather than the 0.8-1.0 second time frame that current tire changers take during pit stops.
Higher torque is one of the main reasons that the pit gun is able to take off the single lug nut in a faster manner. Pit crews definitely could range back to only needing 10 seconds for an ordinary pit stop under this new practice.
"Nobody's done it, so I'm not sure anyone can have an informed opinion on how it's going to affect them," Probst said. "But there's still a premium on getting from the pit wall to the right hand side of the car. That's not going to change. You're still going to have to get the nut off and back on as quickly as possible. That's not going to change. You're going to have to go from the right hand side to the left hand side of the car as quickly as possible."