Is it safe to drive car making grinding noise before 4th mount is replaced?

What is your question?

Rumbling noise during acceleration. Only 3 out of 4 mounts were replaced by mechanic, causing imbalance.

What makes this problem better or worse?

Worse when accelerating gas, especially on incline

How long has your 2002 Volvo V40 had this problem?

It started after car was serviced, 3 mounts were replaced