While battling for tenth place with 55 laps to go, Richard Childress Racing Chevrolet driver Dillon and his former team-mate Reddick made contact entering Turn 1 as they ran three-wide with Brad Keselowski to their outside.
Dillon was the only one who lost out, spinning across the track and slamming the outside wall.
The 2018 Daytona 500 winner was able to climb from the car under his own power and decided to show his displeasure with Reddick by tossing his helmet in the direction of the 23XI Racing Toyota.
After being checked and released from the infield care centre, Dillon took issue with former driver Dale Earnhardt Jr's analysis on television replays putting the blame on him for moving down on Reddick.
Reflecting on the “pretty rough hit”, he told NBC Sports: “I heard Jr.’s replay said that I came down a little bit. I felt like I was holding my own.
“[Reddick] was at my left-rear going in there, and I knew we were three-wide. I think I’ve got the right to at least hold my lane.
“I’ve got to turn at some point to get down. Brad was on my outside, maybe a half-lane up.
“But Tyler drove it in there, and obviously I feel like he drove it in deep enough where he had to come up the track into me.
“We can look at the SMT and see the little fine movements that we make, but I felt like that was not the time to do that for the #45.”
When asked if the helmet throw was enough, Dillon concluded: “No, I just need to start wrecking some people.”
It's not the first time a driver has tossed their helmet in the direction of a rival's car in anger. Tony Stewart famously did it to Matt Kenseth after the veteran drivers wrecked while battling for the lead at Bristol in 2012.
Discussing the tangle, Reddick said: “He just tried to I think beat me into the corner a little bit and came down on myself.
“By the time I realised what was happening it was too late and the contact had already taken place.”
Reddick went on to finish second but lamented NASCAR delaying a decision to throw a caution when Ryan Preece spun on the penultimate lap. The caution flag was only waved once leader Denny Hamlin had started the final tour, ending the race without going into overtime.
Reddick had fresher tyres than his 23XI co-owner's winning Joe Gibbs Racing Toyota, who was booed after clashing with Kyle Larson at the final restart, and believed he had a shot to win in a green-white-checkered scenario.
Admitting he was “pissed off” to finish second, Reddick said: “There's a car stopped in the short chute before they took the white flag and they didn't throw the caution, so I don't know what that shit is about.
“We had tyre advantage, and we were just eventually going to get up through there.
“We weren't getting any help, unfortunately on the restarts, any pushes. That really put us behind.”
