At General Motors’ Bedford Casting Plant in Indiana, a 10-speed transmission case rests inside a large, cabinet-sized scanner. The machine hums to life. Around it, an X-ray source and detector rotate, capturing thousands of cross-sectional images. Those images are then stitched together into a detailed 3D view of the part’s interior. This is not a concept or a future idea. This is how GM inspects critical components before drivers ever see a whole, say, Chevy Silverado.

If the tech sounds familiar, well, it is. Computed tomography, or CT scanning, is best known from hospital settings, where doctors use it to look for fractures or tumors. 

In GM’s case, the goal is to catch defects inside cast metal parts. Engineers look for signs like porosity, air bubbles, or shrinkage gaps that weaken the structure. The 3D data can also guide machining corrections and improve manufacturing accuracy.

GM started CT scanning in Bedford back in 2019

GM says it helps them make better parts more efficiently. 

Engineers run the machines up to 18 hours a day and assist other GM sites by scanning components remotely. In a recent press release, the company highlighted this technology as a major step toward better quality.

But some owners may find that claim difficult to reconcile with recent recalls

In April 2025, GM issued a 600,000-vehicle recall for its L87 6.2-liter V8 engine. 

The engine appeared in full-size trucks and SUVs from 2021 through 2024, including the Silverado, Sierra, Tahoe, Yukon, and Escalade.

Complaints poured in about engine knock, bearing failure, and total loss of power. GM acknowledged over 28,000 cases, or “field complaints,” before the recall. Some engines needed full replacements before hitting 30,000 miles.

The root cause involved connecting rods and crankshafts that had been cast or machined out of spec.

In March, GM recalled over 90,000 vehicles with its 10-speed automatic transmission. 

Drivers experienced sudden downshifts and harsh shifting. In rare cases, the rear wheels locked up during motion and even damaged the engine beyond repair. 

GM traced the issue to premature/excessive wear in the transmission’s valve body. That component requires high-precision casting and fluid control.

MotorBiscuit reached out to GM, which confirmed CT scanning wasn’t part of building the L87 V8

Bill Grotz, Senior Manager of Global Public Policy and Regulatory Communications at GM, responded to my email on the recent recalls and whether CT scanning played a part in their approval.

He said that CT scanning is exclusive to the Bedford operations, and as such, only four-cylinder engine blocks are scanned. Scans are also performed on “transmission cases, structural components and EV drive unit housings.”

Further, Grotz provided clarification on the problems identified with the L87 engine:

“The primary root causes we’re addressing with the L87 engine recall are attributable to two supplier manufacturing and quality issues: (1) rod-bearing damage from sediment on connecting rods and crankshaft-oil galleries; and (2) out of specification crankshaft dimensions and surface finish.”

GM says its current castings are the best it has ever produced. The scanners might support that, but they’re use is limited at the moment and doesn’t play a part in QCing supplier-provided components.

Many customers still feel the sting of recent failures. The only lasting proof of improvement will be seen in reliability on the road, not just precision on a screen.