90 Trooper 4wd not working

I just purchased a 90 Trooper. It is my third one. When I shift the transfer case into 4wd I only get the "4wd" light on the dash to come on. Nothing happening on the front axle. I'm not sure what the steps are for diagnosing this problem. Is it the transfer case or the automatic hubs or ...? Any of you that have experience in this please reply. Legacyman.

I set the Trooper on 4 jack stands and ran it in 4wd. The front drive shaft turns and a clicking sound comes out of the left front wheel. I removed the bolts holding the cover and the snap ring holding the hub. It is well lubed and looked ok so I disassembled the other side and then noticed the difference in the teeth between the two hubs. Just for grins I put the right front hub on the left front and it engaged like it should. After packing the wheel bearings I replaced the worn/damaged hub. It's a very clean, low mileage Trooper from an older couple that was towed behind their RV; not a bad buy for $1,700. LM.
PS. It has a rear drive shaft disconnect on it. I've never seen one of these before. It will be funny to see my teenage daughter try to sneek this out of the garage.

I have a similar situation with my '92 LS.

How did you get the circlips back on the shafts after the clutch assy switch?

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