There is a little guide tab that sticks out of the hub that helps center the rotor, is there a chance you installed the rotors without making sure those tabs were mated to the holes in the rotors?


Because that will cause some wonky-ass brakes. And its a mistake even an experienced wrench can make when they're in a hurry (ask how I know).

Also possible that there was some contamination on your rotors and the "vibration" was the brakes gripping where the contamination was low and slipping on the contaminated parts. You could certainly consider brake cleaner contamination if it didn't evaporate completely.

Double check your lug nuts and make sure that all your brake lines are intact. As long as the pedal feels good and the brakes continue to stop vibe-free and with normal power/modulation I'd consider it a case of post-maintenance shakedown and not worry too much about it.

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'84 300D
'97 Jeep XJ lots of mods
'01 Subaru Forester