Providing your hydraulics are good and your clutch is clearing and you are not to quick on your gearchange then the issue will probably be the synchromesh.
So the answer to your question is No, but the gearbox will have to be removed and stripped to fix the issue.
As what Jack has said, ^^^^ sounds like the beginning of PAS pump failure.
Low mileage pre-owned pumps are in stock depending on what model of 350 you have.
Just drop me a PM if I can help further.
Low mileage preowned fully guaranteed steering racks are in stock at the moment for HR 350Z.
Just drop me a PM if I can help further.
Shipping same/next day.
Alex.