It used to be on the earlier rear wheel drive cars with a solid diff and axle, that the only wheel alignment required was for the front wheels.
But that has all changed with the advent of front wheel drive and independent rear suspension. The rear wheels, like the front ones, also can go out of alignment. When they do, they wear unevenly which sometimes causes ‘ripples’ or ‘scalloping’ on the tread. This results in a noise that sounds like the wheel bearings are about to collapse.
The ‘ripples’ can actually be felt by lightly running a hand around the tyre tread. If you do this yourself use gloves to protect your hands as there might be sharp objects wedged in the tread. The tyres will need to be replaced and the alignment and suspension components checked.
Another cause of noisy tyres is when the layers in the tyre casing separate and cause bulges or bumps in the tread. These can also be felt by running a gloved hand around the tread. A tyre in this condition must be replaced straight away as there is the possibility of a blowout.
So keep an eye out for uneven wear on both front and rear tyres, and if you are worried speak to your mechanic or tyre specialist.