The transfer case skidplate has always been an afterthought in Toyota SUVs and trucks. The other skids (front, fuel tank, and auto tranny) are superb for stock. BTW, the skid for the auto tranny is nice (not seen often in other SUVs)...even though it is tucked up into the body (toyota is thoughtful in that way).
the skid for the transfer case looks similar to the 3rd gen. There are aftermarket skids for the 3rd gen. However, i am not sure if the attachment points are the same.