Team Penske’s investigation into the source of Josef Newgarden’s crash while leading Sunday’s NTT IndyCar Series race at Iowa has reached a definitive conclusion.

“I think it’s all pretty matter of fact from where I sit – the failure was the right-rear shock,” Penske president Tim Cindric told RACER. “That side of the car didn’t even hit the wall.”

Newgarden’s car snapped violently while firing out of Iowa’s Turn 4 and the NBC cameras caught a puff of smoke emerge from the rear of the car as the left-front tire lifted off the ground before impact. All signs pointed to something being amiss at the right-rear.

Damper failures are a rarity in IndyCar. The items that connect to the dampers — rocker arms and pushrods and spherical bearings — are more common in regard to outright mechanical failures. Although it’s not necessarily what happened on Newgarden’s No. 2 Chevy, once a damper is fully compressed and the coilover spring is fully compressed, additional loading can cause the spring to bend into the shape of a U and break the top of the damper off the body.

Regardless of what caused Newgarden’s damper failure, Cindric says the freak occurrence is more troublesome than if the crash had been the result of human error.

“Half of me wishes it was something that you could say, ‘Well, that’ll never happen again, because a bolt was loose, or this happened or that happened,’” he said. “Or maybe it was an old part that broke. But I’m of a mixed mind here because there’s nothing that you would say we should have done different.

“And it isn’t a trick part; we’ve run the same design for a long time. That design hasn’t changed with the part that failed. And the part was well within the mileage limitations of what we set. So we sent it off to an expert to tell us what happened, and we’ve got metallurgists to look at it. There was no crack that propagated from some other accident. So, the reason it failed is unknown. It’s still a mystery.”