Infiniti Q30 noise from the back

[Tomik]

Hello everyone.
I have infiniti q30 2.2 diesel 2016 and I have an issue, maybe someone could help me...
I have bad noise coming from the back of the car and while I am driving 0-15 miles/h it feels like I am going over small humps...
Also, when I completely stop and hold down brakes, it has slight vibration going from the front to the back and in the end it does the same noise one more time.
Mechanic said that I need to look at rear Differential and Haldex.
Has anyone had anything similar? And would any other car brand parts fit my infiniti, as it's basically Mercedes?
Thanks!