Martin Truex Jr. takes pole for Auto Club 400 at Fontana after a third of field fails inspection

Reigning NASCAR champion Martin Truex Jr. won the pole position for the Auto Club 400, but only after more than one-third of the field did not qualify Friday because the cars failed to pass inspection.

Truex, driving the No. 78 Toyota for Furniture Row Racing, took the top starting spot for Sunday’s race with a lap of 186.567 mph on the two-mile Auto Club Speedway in Fontana. Truex won the title last year in NASCAR’s top-level Monster Energy Cup Series.

Kyle Busch, a three-time winner of the Cup race at Fontana, qualified second and Kyle Larson, last year’s winner, will start third. Kevin Harvick, who is riding a three-race win streak, qualified 10^th.

It was an unusual qualifying session because 13 cars in the 37-car field failed to get through inspection in time to qualify, so they’ll start at the rear of the pack.

The non-qualifiers included all four cars of the Hendrick Motorsports team, including the No. 48 Chevrolet of Jimmie Johnson, who holds a record six Cup wins at Auto Club Speedway.

Teams routinely push the limits of NASCAR’s rules, and Busch noted that NASCAR this season is using a new inspection system to scan the cars for any features that don’t conform.

“It’s our fourth week on it and I think we’ve got to give it a little bit more time,” he said.

Busch, who won the Cup title in 2015, also said the inspection systems are “so intricate and so complicated” because “we’ve over-engineered our race cars over the course of the last 20 years by 10-fold, 100-fold, whatever you want to call it” and NASCAR is “trying to keep everybody equal.”

“NASCAR is doing what they need to be doing, and we’re all doing what we need to be doing, and there’s going to be times where our line is past their line, and what they want to allow through, and I think that’s just natural,” said Busch, who drives the No. 18 Toyota for Joe Gibbs Racing.

Farmer John teams with Wallace

Farmer John is jumping on the Bubba bandwagon.

Best known in Southern California for providing the Dodger Dogs at Dodger Stadium, Farmer John opted to be primary sponsor for Darrell “Bubba” Wallace Jr. at the Auto Club 400.

Wallace, 24, is a Cup series rookie driving the No. 43 Chevrolet for NASCAR Hall of Famer Richard Petty. Wallace’s popularity swelled when he finished second behind winner Austin Dillon in the season-opening Daytona 500 in February.

“Knowing that Farmer John is a big deal on the West Coast,” combined with Wallace’s growing fan base and the race’s location in Fontana, “it makes the most sense to have Farmer John be the brand on the car,” said Diana Souder, a spokeswoman for Farmer John’s parent company, Smithfield Foods Inc.

Farmer John sells about two million Dodger Dogs at Chavez Ravine each year, and they became a household name in Southern California because the hot dogs were advertised for decades by legendary announcer Vin Scully.

Smithfield formerly was a primary sponsor for Richard Petty Racing and driver Aric Almirola. Smithfield moved to Stewart-Haas Racing this year and was followed there by Almirola, who drives the Smithfield-backed No. 10 Ford for SHR.

But Smithfield, which in turn is owned by the Chinese company WH Group Ltd., still has a commitment to be the primary sponsor for Petty in six Cup races this season, Souder said. So Smithfield tapped its Farmer John brand for Fontana.

Although this is Wallace’s first full year in the Cup series, he wasn’t an unknown talent to Smithfield. Wallace drove in four Cup races last year as a substitute after Almirola injured his back in a crash at Kansas Speedway.

“We like Bubba a lot,” Souder said. “He is bringing a lot to this sport and we’re happy for him that he got a full-time ride in the Cup series with the 43.”

Wallace has struggled since Daytona, finishing 21st or worse in the following three races. But Wallace said he was undeterred.

“I’m still keeping a positive mindset, looking forward to each and every race,” Wallace told reporters before qualifying 19th for Sunday’s race.

“It’s a learning curve,” he said. “We are just not hitting on all cylinders right now as a team. We are going to have some really good races, we are going to have some bad races, but we are going to keep our heads up and keep digging.”

james.peltz@latimes.com

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