CUP: Clutch issue before start of Sunday’s race dooms William Byron’s run in Chicago

Written By Brock Beard

by Brock Beard / LASTCAR.info Editor-in-Chief

PHOTO: Eduardo Olmos Ayala, @EOlmos

William Byron picked up the 2nd last-place finish of his NASCAR Cup Series career in Sunday’s Grant Park 165 at the Chicago Street Course when his #24 A-Pro Auto Reconditioning Chevrolet fell out with clutch issues after just 1 of the race’s 75 laps.

The finish, which came in Byron’s 271st series start, was his first of the season and first in a Cup race since February 17, 2020 in the Daytona 500, 198 races ago. In the Cup Series’ last-place rankings, it was the 24th for the #24, the 43rd for clutch issues, and the 873rd for Chevrolet. Across NASCAR’s top three series, it was the 43rd for the #24, the 71st from the clutch, and the 1,998th for Chevrolet.

When Byron was last featured on this site, he was just starting his third full-time season in the Cup Series and in search of his first win. He’d soon find it that August in his return to Daytona, the first of 14 wins and counting for the former sim racing prodigy. In the NextGen era, Byron has challenged his Hendrick Motorsports teammate Kyle Larson as the team’s top river, scoring six victories in the 2023 season, claiming the Hendrick team’s 40th anniversary race at Martinsville last year, and making the Championship Four each of the last two seasons. His single win in 2025 also brought him into select company when he joined Richard Petty, Cale Yarborough, Sterling Marlin, and Denny Hamlin as the only drivers to score back-to-back Daytona 500 victories. But heading into Chicago, three of Byron’s last four stats saw him finish 27th or worse.

For the Chicago Street Course, Byron debuted new sponsorship from All-Pro Auto Reconditioning on a paint scheme that resembled both Jeff Gordon’s DuPont 200 Years scheme from 2002 and the #25 UAW-Delphi Chevrolet that Jerry Nadeau ran that same year. In practice Byron trailed only Bubba Wallace with the second-fastest speed of 91.006 seconds (87.027mph). But he then lost control in Turn 10 and smacked the wall with the left-rear, breaking a toe link.

Repairs kept Byron from turning a lap in qualifying, but he still ranked 38th ahead of two others who didn’t take time due to their own issues in practice: 39th-place Chase Elliott, whose #9 NAPA Gold Filters Chevrolet struck the wall between Turns 3 and 4, and 40th-place Denny Hamlin, whose #11 Progressive Toyota blew the engine just moments after he pulled on track.

All these drivers were among the 41 who would contend for 40 spots on the grid, marking the first DNQ in a race other than the Daytona 500 since 2018. Most seemed to anticipate the spot would be decided between Josh Bilicki in Carl Long’s #66 Pure Kick Ford for Garage 66, and Katherine Legge in Live Fast Motorsports’ #78 e.l.f. Cosmetics Chevrolet. In practice, Legge was slowest of the open entries after she spun into the tire barrier in Turn 6. But Legge rallied in qualifying – even after getting into the wall twice more – and secured the 33rd spot, two places behind Bilicki in 31st. Sent home instead was Truck Series standout Corey Heim, whose #67 Robinhood Toyota skated into the wall with his left-rear. The damage was enough to leave Heim with a best lap of 92.506 seconds (85.616mph), over a tenth off Legge’s best of 92.368 seconds (85.744mph). The run happened to take place on Heim’s 23rd birthday.

On race day, 40th-place Hamlin was joined by eight other drivers for unapproved adjustments, including Elliott, Legge, and Byron. Also penalized were 11th-place Alex Bowman in the #48 Ally Chevrolet, 14th-place Kyle Larson in the #5 Valvoline Chevrolet, 24th-place Noah Gragson in the #4 Rasmussen Air & Gas Energy Ford, 32nd-place Ricky Stenhouse, Jr. in the #47 Rate Chevrolet, 36th-place Ty Dillon in the #10 Sea Best Chevrolet, and 37th-place Bubba Wallace in the #23 McDonald’s Toyota. It took some time for NASCAR to get both lines reorganized with Bowman, Legge, Wallace, and Elliott trailing the left lane while Larson, Stenhouse, Dillon, Byron, Legge, and Hamlin were the final cars on the right.

During these same laps, Byron radioed he had an issue with his clutch, but would feel it out more after the race started. He ended up last across the stripe when the green flag dropped, 10.264 seconds back of the lead, as Hamlin and Legge battled for position ahead of him. That gap grew steadily as Byron struggled around the track, and he discussed the possibility of going to the garage. By the time the team decided to bring him in, he’d passed pit entry and completed Lap 1, now 22.604 back of the lead to 39th-place Legge’s 16.826. From there, Byron’s car slowed to about 60mph and tip-toed around the track. On Lap 3, Byron had just lost a lap to the leaders as the crew pushed him behind the wall as the first caution fell.

Further back, Carson Hocevar took the green in 3rd but his #77 Zeigler Auto Group Chevrolet lost ground ahead of a tight pack of traffic. Entering Turn 10, Hocevar clipped the wall to his right, then clobbered the wall to his left, destroying the left-front suspension and sending him spinning. This immediately blocked the path of Austn Dillon’s #3 Breztri Chevrolet, who stopped quick enough to avoid contact. But by now, the rest of the field was upon them. While a few cars escaped to driver’s right, Daniel Suarez’ #99 Jockey Chevrolet ran in the back of Brad Keselowski’s #6 Kroger / Blue Buffalo Ford, Todd Gilliland’s #34 Grillo’s Pickles Ford spun off the nose of Ryan Blaney’s #12 Menards / Dutch Boy Ford, then Will Brown’s #13 Mobile X Chevrolet piled in along with Riley Herbst’s #35 Lucy Toyota. Before the red flag came out, first Suarez, then Herbst managed to keep going, dropping Brown to 39th.

As the wrecked cars of Hocevar, Dillon, Keselowski, Gilliland, and Brown were towed into the garage, Hocevar’s car came unhooked from its tow truck at the garage entrance before it was brought behind the wall. All joined Byron in the “Damaged Vehicle Policy” zone, which was staged at the far side of the garage. By Lap 8, among the cars in the garage, only Gilliland and Byron still had their on-board cameras switched on. Gilliland was declared out on Lap 17, meaning that if Byron could return to the track, he’d pass five cars by completing just two more laps. On Lap 20, moments before the end of Stage 1, the #24 crew dropped the hood and pushed him back. The car rolled to the garage exit and stopped. While it first looked like he’d return to the track, the crew instead pushed him back. “We’re done unfortunately – sorry guys,” said the team. After the crew tweeted the clutch issue wasn’t resolved, NASCAR declared Byron out on Lap 25. Brown, Gilliland, Keselowski, and Dillon completed the Bottom Five.

Hill, Legge, and Bilicki turn heads in the closing laps at Chicago

Making only his 12th career Cup start, XFINITY Series standout Austin Hill in the #33 United Rentals Chevrolet followed up his 4th-place finish in Saturday’s race by taking 9th on Sunday, marking his first top-ten finish in the series. His previous best was a 14th in Daytona in August of 2023.

Further back, a tight battle ensued among several of the sport’s smaller teams. As the leaders completed Lap 74, Cody Ware had climbed to 18th in his #51 Arby’s New Angus Cheesesteak Ford, an impressive follow-up to his 13th-place showing in Atlanta just last week. But heading into treacherous Turn 6, Ware’s brakes failed, and he glanced his car off the wall to try and slow it down before burrowing into the tire barrier. Ware walked away from the wreck and was soon checked and released from the infield care center, though the caution wasn’t thrown by NASCAR for nearly a minute until race leader Shane van Gisbergen took the white flag. Ware ended up 26th.

Ware’s wreck improved Katherine Legge to a 19th-place finish, a strong follow-up to team owner B.J. McLeod’s 16th last week in Atlanta. Legge became the first female driver to finish in the Top 20 since Danica Patrick’s final full-time season in 2017, and earned her own career-best in just her third series start.

Two spots behind Legge came Josh Bilicki, who nearly got Carl Long’s Garage 66 team into the Top 20. Bilicki’s 21st-place finish stands as the driver’s best since August 7, 2022, when he also finished 21st at Michigan. This also stands as the best run for the team in the NextGen car, and the best for that same team on a road course. Bilicki accomplished this despite significant nose damage suffered to his car which cost him speed.

LASTCAR STATISTICS

*Byron’s last-place finish ends a streak of the last six consecutive last-place finishers in the Cup Series declared out due to a crash.

*Byron is the first Cup driver to finish last with just one lap complete since November 10, 2024, when Ty Gibbs’ #54 Monster Energy Toyota wrecked at Phoenix.

*This marked the first last-place finish in a Cup race by reason of clutch failure since June 7, 2020, when B.J. McLeod’s #78 Chevrolet fell out after 3 laps at Atlanta.

THE BOTTOM FIVE

40) #24-William Byron / 1 lap / clutch

39) #13-Will Brown / 2 laps / crash

38) #34-Todd Gilliland / 2 laps / crash

37) #6-Brad Keselowski / 2 laps / crash

36) #3-Austin Dillon / 2 laps / crash

2025 LASTCAR CUP SERIES OWNER'S CHAMPIONSHIP

1st) 23XI Racing, Hendrick Motorsports, Kaulig Racing, Legacy Motor Club, Penske Racing (2)

2nd) Garage 66, Hyak Motorsports, Joe Gibbs Racing, NY Racing Team, RFK Racing, Richard Childress Racing, Rick Ware Racing, Spire Motorsports, Trackhouse Racing (1)

2025 LASTCAR CUP SERIES MANUFACTURER'S CHAMPIONSHIP

1st) Chevrolet (9)

2nd) Ford, Toyota (5)

2025 LASTCAR CUP SERIES DRIVER'S CHAMPIONSHIP

Brock Beard https://lastcar.info
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