2005 Mazda 3 rear end noise

[gmtech1]

https://www.youtube.com/watch?v=Tf-FoGD4UdU

A friend has this noise on her Mazda...any Ideas?

From the rear, she says it goes away when the brakes are applied. I suspect a brake pad issue, but do not have the car to look at...any ideas?

[Towncar]

Yours sounds a bit far gone.. but if it started out as a dull knocking responding to every tiny variation in the road surface, it's most likely your rear Lateral Links (one left & one right) bushings gone bad.

If your lucky they last about 80k to 100k miles.. no biggie, it a normal wear item that takes quite a bit of abuse. The sell for $20 / $30 depending on brand name and where you get them. Easy to replace.