Last month’s revelation that Mercedes was temporarily discontinuing most of its V8 models in the U.S. would have been earth-shattering news five years ago.

But given the mess Covid, the shortage of semiconductors, and global logistics problems have caused other carmakers, Merc’s explanation that supply chain issues were to blame seemed entirely plausible.

Now though, it appears that quality issues could be the true culprit. At the Munich Motor Show Road & Track sat down with Mercedes’ Head of the Top End Vehicle Group Philipp Schiemer, who seemed to suggest an alternative to the company’s official stance.

“I cannot provide you with more details. It’s a quality issue,” Schiemer told Road & Track. “We are updating our vehicles every year, and we are not satisfied with the quality. And for us it’s quality first. So we have to do some retesting and this is the process we are in at the moment. So it depends from model to model…it’s from vehicle to vehicle, from country to country a different kind of situation.”

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When the title asked Schiemer if he could go into more detail about the quality issues, he simply replied “No.”

As Road & Track notes in its story, it’s difficult to reconcile Schiemer’s explanation that quality issues are to blame with his assertion that the problem doesn’t affect all cars and all markets.

V8-powered cars account for a much bigger percentage of Mercedes and Mercedes-AMG sales in North America than they do in Europe, and the withdrawal of big-engined GLC, GLE, E-Class, G-Wagens will leave a big hole in the Benz’s U.S. model range. But the new S580 is still available, and Aston Martin, which uses AMG V8s in its Vantage, DB11, and DBX SUV, has gone on record as saying it won’t be affected.

Like Road & Track, we’ve asked Mercedes if it can shed more light on the situation, and will update the story when we hear back.