Loose rotor.

I have a 98 AWD explorer and just found out that the passenger rotor is loose and make a clicking noise when I drive. I don't know why it's loose and would like some thoughts on it. Thanks.

If the rotor is loose, then your wheel should be loose too.

sounds like a broken hub bearing

I think I know what the problem is but I just don't know how to fix it. I took the rotor off and spun the hub and its not clicking so I put the rotor back on and noticed that the hub can move a little inside the rotor. So I think it's the wheel studs are banging back and forward in the hole in the rotor.

The wheel lugs hold the rotor tight to the hub. If in fact the rotor is moving, then the wheel is loose also.

i am going with a bad hub,,, i bet you have an abs light on too,,

So I took some advice and decided to replace the hubs thinking that was the clicking noise I was hearing. But after I replaced the hubs it still has the same clicking noise. I have no idea what it could be now.