Ok. for search purposes 2007 gl450 transfer case removal noise clunking under acceleration .
I was able to complete the job. It was actually a pretty simple task. I was thinking there was more to it than there really was.
If you get the noise in the video, it is your transfer case.
https://www.youtube.com/watch?v=GopnQbbafGA
it progressively got worse as the days went by without addressing it. So I find a transfer case on ebay for 550. I went to a shop and they were going to install a refurbished one for 3500 for just the transfer case. I didn't ask about labor as this was not an option for me.
-remove the 6 size 55 torx bolts for the front drive shaft.
-remove the 6 size 55 torx bolts for the rear drive shaft.
-remove 8 bolts using e12 torx socket for the transfer case to tranny. There are 2 bolts up high on top of the transfer case that are difficult to reach. Having an assortment of extensions and U joints helped. the driver's side is more difficult to get to. Use several long extensions and 2 u joints. go from the back of the transfer case and thread a few extensions with the u joint and socket on top of the tranny towards the front on the drivers side. once you see the extension attach the ratchet with another extension and u joint and remove the bolt.
-with the rear drive shaft unbolted, you will need to get it out of the way to be able to get the transfer case out with a swift blow of your palm, you can force the drive shaft up and out of the way.
The transfer case can now be removed. it doesn't weigh to much so you can just pull it out.
putting it back in is just the reverse. This should only take about 5 hours to complete depending on the needs of your kids as they yell "daddy, can you play with me?"
Now, I had gone the long route as I started disassembling the drive shaft at the rear diff. I also unbolted the center bearing as I thought this was hanging up my driveshaft prohibiting me from removing the transfer case. So when I was able to force the rear driveshaft up and out of the way, the drive shaft was disconnected at the center bearing. I do not believe you need to do this.
In any case, the transfer case seems to operate as it should.