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TJ Enthusiast
on one of them I definitely felt some rusty grinding when spinning it.
That's probably the guilty suspect.
Personally, when I replace idler pulleys, if there are two and only one is bad, I replace both. So, you should be in good shape for awhile on that issue....till the next one pops up! It's a Jeep so it'll require regular repairs! It's all good.....fun projects.