Yep, do your research and make sure you follow torquing requirements for application and you will be fine. Some applications use stretch bolts and you have to replace them along with the part it is holding.
Are these original pulleys/idler, etc...? Reason I ask is wifes GLK is coming up on 150k miles and I was trying to decide when to change them as a preventive measure. She is fine as long as she ain't sitting by the road with a broke down MB
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