Wondered if anyone can help me?

Just had major engine rebuild, got car back (98 Type R Import) now have very loud noise coming from gearbox/front diff area, when off the throttle between 2500 and 3500 revs.

Am confused as it did not make this noise before it went in for rebuild????

Is this just coincidence? or has something not been refitted correctly?

When spoke to the company, reply was, mechanic will have a look when you come in for the 1000 mile oil change.

Does this mean they are liable for any damage caused during this 1000 miles????