Our car makes a squeaking noise when we start it in the morning. The same thing happens when the car is parked for few hours. However, there is not any noise when the car is parked for a short period of time or when the engine is turned on and off within few minutes. In addition, it is hard to get the lever from the Park position to the Drive position. At least for now, there are not any signs of mis-behavior during driving.
Squeaking isn’t usually associated with start up noise. I doubt that it would be associated with the transmission. I would probably remove the drive belts and see if the noise remains. About the only time I’ve heard a squeal other than a belt type thing, was in EXTREME cold and it was a manual with the clutch pushed in.
Can I assume that the Infiniti’s selection follows the traditional PRNDL or PRND2L? You didn’t mention issues with the other ranges nor difficulty from Drive to any other position. I’m not acquainted with the i30, but normally this would be a simple cable adjustment.
Transmissions do not make noise when the engine is being started.
If it made noise when you put it in gear, or started driving it, then that could be caused by the transmission.
Do you park on a slight hill when the transmission is hard to get out of Park?
Have you tried putting on the emergency/parking brake before you put the transmission into park, and shutting off the car, to see if that makes the car easier the next day to take it out of Park?
You should try that first, here’s the steps:
When you get to your parking spot, with the engine still running, and the car still in D, do the following:
Activate parking/emergency brake, as much as you can.
Put car into P.
Shut off engine.
Go about your normal life.
Come back to car the next time you normally need to use it.
Put car into D. (was it easier?)
Release parking/emergency brake.