It was making the noise before the tires were installed. He did say the belt was really really right so he loosened it to where it should be. I thought maybe wheel bearing but they didn't notice anything on installing tires. But it makes a racket when driving and I certainly hope it's not what they "suspect" it to be. The output shaft bearing. It has all the power, shifts through all gears with no problem. Just makes a cranky racket when moving. Not gear or speed specific.