I just replaced front pads and rotors. I expected the new rotors (Beck-Arnley, purportedly very good quality) to just freely slide fully onto the hub. But they were hard to get fully onto the hub. Actually, once they were fully on, I could not pull them off by hand. I am afraid that the next time I try to remove them that not even a sledge will break them loose. I've been doing brakes for years and never encountered this. Thoughts?