the car has now a noise like (clack clack clack) under the car in the rear only under acceleration at low speeds.

what can it be? the diff? a shaft? rod?

 

does it go with engine speed or vehicle speed? could be many things, even the a broken EGR pipe has a noise (with engine speed).

 

with vehicle speed. sounds under the car in the rear and i kinda feel it. I replaced wheel bearing, diff, axle and still but just a little and only sometimes

 

Did you check the condition of the transmission mount? Wasn't it cracked?
Does your noise synchronize with the movement of the shift lever? This can be checked by touching your hand to the shift lever and accelerate. If the movement and the noise occurs simultaneously, it is caused by the transmission mount in most of the case.

 

A much simpler thought if this has appeared suddenly, is there some hard object stuck in the tire? Rock, big screw...