I have xtrail overheated and all coling system replaced 'chains'guides and tensioners all of sudden grinding noise chain on metal
My car has a manual transmission.
If the noise started just after repairs than it is possible that it was due to something that was removed from the engine during the repair, but it could also just be a coincidence. A qualified technician will be able to diagnose the grinding noise in person and perform any repairs required. They will look over all the the parts mentioned as well as check the chain guides and tensioners.