Ended up being that they were
under torqued. It was pretty much my first time ever doing brakes / new rims / whatever and I only used a torque gun, which didn't do the job.
The root cause was that I used lug bolts that were not designed for the application.
I was very fortunate that my coworker pointed it out so that we could fix it, before I ended up losing a tire at 85 MPH on my commute to work.
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lugs cracking because they aren't deep enough and aren't meant for these rims
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comparison of the grooved back of the rim in the 6 lugs used for Chevy, vs the universal ford or dodge ones
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