IIHS’s tougher crash test found a rear passenger’s head nearing the front seat in a GMC Canyon

The 2026 GMC Canyon crew cab earned an overall Marginal rating in the Insurance Institute for Highway Safety’s updated moderate overlap front crash test, after the rear-seat dummy’s head moved close enough to the front seatback to raise the risk of a head injury. IIHS scored the AT4 Crew Cab’s rear passenger-side head and neck protection as Marginal, a drop from the Good rating the same truck earned under the institute’s original, driver-only version of the test. Its front-seat protection stayed Good across every measured category.

Rear-seat injury measures behind the Marginal grade

IIHS ran the test on a 2026 GMC Canyon AT4 Crew Cab 4wd, positioning a dummy representing a small woman or 12-year-old child in the second row alongside the usual driver dummy. The rear dummy recorded a neck tension of 2.7 kN, a chest compression reading of 0.5 kN, a chest injury index of 40, and a shoulder belt tension of 5.7 kN. IIHS rated the rear dummy’s chest protection Acceptable and its thigh protection Good, while its restraint and kinematics score came in Acceptable.

The Canyon’s ratings away from the crash tests were mixed as well. IIHS rated the truck’s headlights Acceptable and its seat belt reminder system Good, but scored its front crash prevention system Poor in vehicle-to-vehicle testing and Acceptable in pedestrian detection, a gap GM Authority’s breakdown of the test data noted means the AT4 Crew Cab’s forward-collision warning and automatic braking still miss more real-world scenarios than the institute considers acceptable for a top score.

The front-seatback problem IIHS flagged

The head and neck measurement is what pulled the overall grade down to Marginal. “The rear passenger dummy’s head approached the front seatback during the crash, increasing the risk of head injuries,” GM Authority reported, describing footage of the test. IIHS’s own rating page for the 2026 Canyon crew cab lists the rear passenger-side head/neck result simply as Marginal, one step below Good on the institute’s four-level scale.

Every other rear-seat category on the Canyon avoided that penalty. The driver dummy came through with Good ratings for head/neck, chest, and thigh/hip protection, with only its leg/foot measure landing at Acceptable, and the truck kept a Good rating in IIHS’s updated side-impact test. The gap between a Good driver score and a Marginal rear score is the pattern the updated test was built to expose.

A test redesigned after finding rear passengers at higher risk

IIHS introduced the second-row dummy into its moderate overlap evaluation in December 2022 after its own research found that back-seat passengers faced a 46 percent higher risk of fatal injury than front-seat occupants in vehicles built since 2007, despite decades of improvement in frontal crash protection aimed mainly at the driver’s seat. “This is a fantastic opportunity to rapidly deliver big safety benefits by adapting technologies that [researchers] already know to be effective,” said Marcy Edwards, the senior research engineer who led development of the test.

The institute adjusted its scoring criteria again in February 2024 to better account for how rear shoulder belts sit on occupants of different sizes, the change that applies to the Canyon’s 2026 result. A vehicle now needs strong scores in both the driver and rear-passenger measures to clear the moderate overlap test with an overall Good rating.

The Canyon’s midsize-truck peers scored little better

The Canyon is not the first midsize pickup to struggle with the rear-seat measure. When IIHS first ran the updated test on five crew-cab pickups in 2023, a 2022 Chevrolet Colorado, built before the current generation the Canyon now shares a platform with, came away with a Poor overall rating, and only the Nissan Frontier among the group managed an Acceptable score. “[IIHS’s] updated moderate overlap front crash test proved to be challenging for small pickups,” IIHS president David Harkey said at the time, adding that rear seat belts across the class needed improvement.

Full-size trucks have not fared much better under the same measurement. When IIHS tested four large pickups in November 2023, three of them, the Ford F-150, Ram 1500, and Chevrolet Silverado, rated Poor overall, and only the Toyota Tundra reached Marginal. “Like most other vehicle classes, large pickups don’t perform as well in the new moderate overlap evaluation as they do in the updated side test,” Harkey said of that round of testing, pointing to excessive lap-belt submarining as the common failure across the group.

IIHS has not yet published an updated moderate overlap result for the current-generation Chevrolet Colorado, the Canyon’s closest mechanical sibling, under the same protocol. The Canyon’s own rating stands at Marginal overall, pulled down by the one measurement IIHS added specifically to track the passenger sitting behind the driver.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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