Hello,
I am trying tonget my '78 Santana 109" with a 200tdi-lt77-lt230 up and moving after years. I thought I had it, but the monster has other plans.
Here's the issue in as much details as I can muster:
I shift into gear and I have no drive. I just installed a new clutch master and slave and they seem to be working.
The front drive shift spins, but the rear does not.
There is an intermittent knocking noise from the transfer case. It seems to come from right at or inside the axle brake drum. The drum itself twitches with the noise.
It will occasionally "catch" and cause the vehicle to lurch (forward or reverse)

I don't know anything about this stuff so feel free to talk to me like an idiot. My gut feels like whatever connection from the transfer case to the rear drive shift that is in the axle brake drum is broken.. . But that's just an uneducated guess. I could really use a hand.

OK so first lesson on how the Lt 230 works. It is a permanent four wheel drive system where drive is sent to all four wheels at all times. To allow for different wheel speeds you have the normal differential's in the axles and to allow different wheel speeds front to rear there is another differential inside the lt 230.
This center diff has a lock so when using vehicle off road drive is sent 50/50 to both axles.
An issue is many folk do not understand that this is not an axle locker, its job is the same as when you put a more usual 2x4 system into 4 wheel drive.
An issue is that when center diff is in its normal open road going position should any of the four wheels not be on the ground all drive will go the easy way to the wheel in the air, hence the lock for off road work.
Because your front shaft is spinning this says there is an issue with the front axle.
To test put the transfer box into lock and main box into gear and gently see if it drives. Come back when you have done this.