I have rebuilt two fuser units for this model in the past year or so and have had problems with both. Each one of them popped the upper hr bearing and smashed the lamp. The funny this is I have just figured out why. I am used to rebuilding the larger fuser units i.e 6570 ,e550 e520 etc and tightening the fuser pressure screws all the way. This is not the case with the 4560 as i have obviously found out. Just thought I would pass this on. Hope it helps Cheers