While driving there was a grinding noise when attempting to shift the transmission into park?

Hello,
I was driving my truck listed above 1500, when I heard a grinding noise. I got to a red light and all of a sudden, the truck would not drive when pushing the gas (the light turned green). The truck left me stranded and when I put the truck into park it made a whining noise. This truck is basically brand-new help! I had my husband look underneath as I had to get towed, he stated the transfer case was cracked and leaking oil. Do you think if we replaced the transfer case the truck would be fixed or am I looking to have to purchase a brand-new transmission?