Took my g37x in for a differential service under warranty, they are replacing the rear and the transfer case. I asked if they are doing the front as well and they informed me that it was part of the transfer case. This seems to be incorrect but this is the first time iv changed these fluids. Any input, and does the front differential need to be changed often? The rear probably takes the trauma the most, not engaging the front unless the rears slip. The car does have 109k miles on it and from what I can tell, the diff fluid has never been changed.

 

The front differential is not part of the transfer case. The front differential sits next to the engine oil pan.