Way to manually engage/disengage the LR3's center diff/transfer case actuator?

[proslambanomenos]

Question first: 07 LR3 - If i remove the rear driveshaft, is there a way to "force" engage the transfer case actuator manually so the center diff still sends power to the front axle when the rear drive shaft is removed (perhaps by tricking the actuator into position somehow, or by using the gap diagnostic tool that i have to force it into position, etc)?

Context: I'm getting some rotational clanking and characteristic driveshaft imbalance vibration at some speeds when the vehicle is under load (throttle depressed, etc). I believe it's being caused by a failing hinge joint on the rear diff side of the center bearing mount (hopefully this description is clear!), and i'm thinking of doing a couple things to diagnose after removing the driveshaft:

1) inspect the bearing as much as possible off the truck without cutting into it. from below (while still mounted) it looks like the boot sealing the joint behind the center bearing has already torn a little and possibly some debris has made it into the joint area causing mechanical damage, or moisture/corrosion from exposure, or both.
2) try driving the vehicle with the rear shaft removed and see if the noise goes away (i realize this doesn't eliminate the possibility that i could be having rear diff issues, but the sound seems to be too far forward for it to be rear diff).

Also, if any of you have any additional suggestions for ways to diagnose this, please advise!

The curious/frustrating thing is, I replaced this driveshaft a little over a year ago with a BritPart unit from Lucky8LLC. Not sure if this is a problematic brand or not, or if they warranty their driveshafts. But before I pursue that course I want to verify it is in fact the driveshaft.

Thanks!

 

[douglastic]

Doesn't selecting "Grass/Gravel/Snow" or "Rock Crawl" lock the diffs?

 

[remember5]

OMG. 30 minutes of my life I'll never get back but I now know how complex the 4wd system is, .pdf attached. From what I just read there really is not a "lock" of the transfer case but a clutch pack that compresses to offer close to a lock but it's all controlled by the shift motor and two sensors reading into the transfer case ECU. That is to say I think Doug is correct, you would have to try to accomplish what you're trying to do electronically. Usually if a U joint is shot or a double carden yoke, it's readily seen by really shaking the joint with no pressure on it. In other words all 4 corners in the air. And as a side note, I replace my front and rear and the carrier with Genuine from LR Merriam.