Joe Gibbs Racing is confronting a significant reliability challenge at a pivotal moment in the NASCAR season, as a series of Toyota engine failures during the Xfinity 500 at Martinsville Speedway has unsettled the team’s charge for the 2025 Cup Series Championship. The Joe Gibbs Racing reliability crisis emerged just as JGR looked poised to cap off their dominant playoff run before the critical Phoenix finale.
Toyota Engine Failures Disrupt Joe Gibbs Racing’s Momentum
During Sunday’s tense 500-lap Xfinity 500 at Martinsville Speedway, engine problems struck hard across the Toyota camp—impacting three separate cars, including those of JGR’s Denny Hamlin and Chase Briscoe, as well as Riley Herbst. The event, dubbed The Paperclip, was a dramatic playoff elimination race, ultimately won by William Byron, who locked in his place among the Championship 4.
Joe Gibbs Racing arrived at Martinsville as the top playoff performer, having won five of the prior eight races. Instead of solidifying a pre-finale advantage, the team was hit with unexpected technical failures at a stage where resilience should be peaking.
Denny Hamlin, already through to the Phoenix finale following a crucial Las Vegas victory, battled mechanical woes for much of Sunday’s race. Meanwhile, Chase Briscoe’s engine issues forced an early retirement after 295 laps, relegating him to a last-place finish. Riley Herbst, another Toyota driver, exited prematurely as well, making it three Toyota engine failures in one race—compared to just one engine-related DNF at Martinsville over the previous six events.
Describing his struggles, Denny Hamlin said:
“It’s just because the engine’s just shut it all the way off… It’s like that where, you know, no noises, no anything, the engine actually cuts off. But I don’t know. Way too early to speculate, I’m sure they’ve got an idea of what’s going on.”
— Denny Hamlin, Driver
Looking ahead to the season finale, Hamlin reflected:
“I can be worried, but I can’t do anything about it. So I’m still optimistic we’re going to go there and put our best foot forward and I’ll be prepared.”
— Denny Hamlin, Driver
Both Hamlin and Briscoe secured Championship 4 berths despite the setbacks, joining Hendrick Motorsports’ William Byron and Kyle Larson for next week’s title showdown at Phoenix Raceway. However, the emergence of sudden, unexplained reliability issues has cast a cloud over JGR’s preparations for the biggest race of the season.
Christopher Bell’s own playoff exit compounded the situation, raising questions about whether the technical adversity seen at Martinsville could be repeated at Phoenix, where high temperatures and mechanical durability will again be put to the test.
Phoenix Finale Confronts JGR With Engineering and Strategic Challenges
For Joe Gibbs Racing, reliability challenges are not entirely new—persistent mechanical issues have shadowed their recent campaigns. Denny Hamlin’s No. 11 car, for example, experienced a starter problem that almost prevented him from qualifying at Martinsville. The team has wrestled with a host of other glitches, including battery and clutch issues, in the last few weeks and continues to determine the precise cause of the latest failures.
Former Hendrick Motorsports crew chief Steve Letarte offered his perspective on the engine issues facing the team:
“The engine not as much. Briscoe the same way. I’m sure there’s more to the story than we know. It’s funny that the two cars locked in broke engines, right? So, it just seems a little odd to me. It’s not that. It is: the car won’t fire for qualifying. Talladega has a throttle sticking. Kansas, it has a power steering issue. Like, there’s a lot of mechanical gremlins circling this 11 car.” (41:11 onwards)
— Steve Letarte, Former Hendrick Motorsports Crew Chief
Phoenix Raceway, venue for the season’s climactic contest, is renowned for exposing both driver resolve and engineering precision. TRD (Toyota Racing Development) engines have proved to be among the most powerful and reliable throughout the 2025 season, with a remarkable 13 race victories, but the failures at Martinsville served as a cautionary signal that the margin for error is razor-thin during the campaign’s final stretch.
William Byron and Kyle Larson—both representing Hendrick Motorsports—arrive in Phoenix in top form. Byron carries an 8.0 average finish and one win at the Arizona track, with three top-five results in recent years. Larson’s record is nearly as impressive, with a 10.1 average and four top-fives since the debut of NASCAR’s Next Gen car. By comparison, Denny Hamlin holds a 10.9 average and just one top-five since 2022 at Phoenix, highlighting the challenge JGR faces. Chase Briscoe, making his first title-round appearance, has struggled at this circuit, finishing outside the top 20 in three of his last four attempts.
While the battle for the Bill France Cup is set for next weekend, all eyes are on Joe Gibbs Racing’s engineering teams and Toyota, which are now under tremendous scrutiny to deliver trouble-free performance when it matters most.
If the Joe Gibbs Racing reliability crisis reappears under the pressure of the Phoenix championship showdown, it could dramatically impact the outcome—not only for JGR’s title hopefuls but for the broader manufacturer championship. The urgency for solutions has left the team and its fan base on edge, as Joe Gibbs Racing aims to recover in time for the season’s most critical moment.
.@dennyhamlin says there was no warning signs for his abrupt engine failure and DNF from @MartinsvilleSwy while he was running 2nd. #NASCAR pic.twitter.com/H0gpmrHaXP
— Peter Stratta (@peterstratta) October 26, 2025
