I know that question has been asked a hundred times so forgive me. I just wanted to make sure with my layout and for code that I was doing it right. If it makes a difference for the code requirements I line in NJ. I am running a 100 amp sub panel from my basement to my garage. I would prefer to use copper wire, should I use #2 THHN or #4 and what should I use for the netural and the ground. The run is going to be about 125' and it will all be indoors. I assume that since my garage is attached I will not need grounding rods. Thanks for your help.

Vinny

Typical would be #4cu or #2al SER cable.
No, no ground rods are needed at the sub-panel.

I agree with Stan