My head is in the machine shop, and the machinist said he has had issues with German diesels stripping threads when removing glow plugs, is that a common issue with these CRDs?

It happens.
Can’t really say it’s common.
You’ll know as soon as you attempt removing them.
Either they come out clean or they don’t.
To prevent this, put anti seize on the glow plug threads.

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U.S. Army Retired

I would say it is not common on these vehicles.
Several on here have reported the glow plug snapping or breaking off when trying to unscrew it out of the head.
Not a huge problem as they make tools to extract them when this happens.
Don't believe I remember anyone reporting the threads coming out with a glow plug.
As Flash said, anti-seize is your friend, especially when screwing steel into aluminum....

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Supporting Vendor and Moderator of LOST
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