transfer case?

[JOEEZXJ]

why is my 1990 xj's front drive shaft rotating when it is 2wd

 

[sleeperjeeper]

my guess would be that the front hubs are locked which turns the axles which turns the drive shaft, even though no power is being applied to it. but that's just a guess.

you could put it up on blocks and test it to find out.

 

[joe_peters]

my guess would be that the front hubs are locked which turns the axles which turns the drive shaft, even though no power is being applied to it. but that's just a guess.

you could put it up on blocks and test it to find out.

OP, do you have a hub conversion on your XJ?

OP, which transfer case do you have? D30 CAD vacuum disconnect front axle?

 

[Begster]

As Joe was getting at, you probably have a NP242 transfercase (2WD - 4 Part Time - 4 Full Time - N - 4 Lo), which does not use a vacuum actuated (CAD) front axle. Therefore the front drive train is always spinning.