Ok question. Just completed a 1600 mile trip to the CO mountains and back. Ready for a 2500 mile oil change and thinking about changing the T-case as well. I know it's not reccomended normally until around the 30k mark, but with a lot of people commenting of failures. low levels from the factory (mine was about 9-10oz low), and even some comments about maybe more frrequent changes to prevent failure is wise, or overkill? With the dealer parts delays even more so post strike than pre strike, I'm just soliciting opionions and experience of frequency of T-case fluid change to avoid delays of continiual daily driving fun!