The 18-year-old Garcia from Monroe, California, joins ThorSport Racing following his first full-time campaign in the Truck Series with McAnally-Hilgemann Racing in 2023.
The 18-year-old Gray from Artesia, New Mexico, becomes the fourth TRICON Garage competitor to be retained by the team for the 2024 Truck Series season.
The 32-year-old Poole from The Woodlands, Texas, will be piloting the No. 44 Chevrolet Camaro for Alpha Prime Racing on a full-time basis for the 2024 Xfinity Series season.
The 21-year-old Heim from Marietta, Georgia, was fined $12,500 and docked 25 points for intentionally wrecking title rival Carson Hocevar late in the finale following an earlier on-track incident.
The 29-year-old, third-generation Blaney from High Point, North Carolina, outdueled title rivals Kyle Larson, William Byron and Christopher Bell to become the 36th different competitor to win a Cup Series title following a runner-up result in the 2023 finale at Phoenix.
The 2014 Cup Series champion from Bakersfield, California, led 23 laps en route to earning a top-10 result in his 826th and final career start as a full-time NASCAR Cup Series competitor.
The 21-year-old Gibbs from Charlotte, North Carolina, recorded four top-five results, 10 top-10 results, 112 laps led and an average-finishing result of 18.4 en route to becoming the fourth different competitor to win a Cup rookie title for Joe Gibbs Racing.
The 25-year-old Custer from Ladera Ranch, California, led a race-high 96 of 202 over-scheduled laps and capitalized on an overtime shootout to win the finale in the desert state and become the 33rd different competitor to win an Xfinity Series championship.
The 19-year-old Smith from Johnston, Iowa, notched his first career victory at Phoenix in March, made the 2023 Xfinity Playoffs and finished sixth in the final standings during his first full-time campaign in the Xfinity circuit with Joe Gibbs Racing.