Sound in the bar sector by taking out the "cluth

Hi how are things! ... greetings to everyone ...

I have a Suzuki Grand Vitara 2007 (Motor 2000). 4x4

The problem:
when taking out the "cluth" after changing, a sound or pounding is heard in the bar or transmission tree sector ... and very rarely does it when I put the "cluth" to make the change of march.
The mechanic has already reviewed the differential and the transmission bar or tree and says that it is in good condition, but fails to find the problem.
Could someone guide us a bit?
What feet or areas are this sound or hit when the cluth is removed?

Thank you very much for your suggestions.
Greetings