Need help with transfer case problem....

[MidnightH3]

Hello, I'm a new member here and just got an 07 H3 auto with the adventure package last Tuesday. Last night I was testing out the different 4x4 modes in a dirt field, when a problem came up. The transfer case shifted fine from 4 hi unlocked to 4 hi locked to 4 lo locked, then back through until it got to 4 hi unlocked. When it tried to shift back to 4 hi locked, it started making a grinding noise like someone who can't drive a manual. It would shift back into 4 hi locked and 4 lo locked just fine, but every time I try 4 hi unlocked, it makes that terrible grinding noise. I had to limp it home in 4 hi locked, but I kept it under 40 and kept the turning to a minimum. It has a 3 month warranty through the dealer I bought it from that covers the transfer case, but I wanted to ask here before I took it down there. I searched the forums and came across the TSB 3424 about the transfer case not completing shift but I haven't found what the bulletin actually says. So any ideas or help from anyone would be greatly appreciated, thanks!