It is best to contact a certified Jeep mechanic for all repairs to prevent damage to your vehicle.
Yes.Yes.
Yes
It will turn when driving because there isn't a disconnect from the front axle. It should be disconnected inside the transfer case.
It will turn when driving because it is still hooked to the front tires. The only disconnect is on the transfer case.
You can if you remove the rear drive shaft.
Its the rod from your front tire to the drive shaft their is one on each front tire
The universal joints in the front driveshaft may be going bad.
That would indicate a bearing or drive component going bad, could also just be one of the front U joints. When tension is applied the pieces will take up the slack from wear and sound fine, then when you remove the force from the driveshaft on the components they move all around making that grinding noise. You should get that front differential looked at soon. To test the U joints climb under the jeep and try to rotate the front shaft, if you can feel movement or jiggle it at all the U joint is bad.
How do you change the steering shaft in a 1990 Jeep Wrangler?
See if your drive shaft going to front end is bent.
The Prop shaft (front drive shaft) has a ball type cv joint that sits in bearings that connects to the transfer case. This is most likely shot and you need a front prop shaft (front drive shaft) complete with rubber boot and differential cv universal joint.
If you did the drive shaft would not hook up and you would have no steering ability.