Land Rover Repair: 2001 Land Rover Discovery 4wd problems, land rover discovery, penetrating oil

Question
My sister-in-laws discovery will not shift into 4wd, is there a common problem with this particular model that I need to tell my brother about...he is already dealing with air suspension with his range rover, and just switched the suspension on his wifes discovery from air bags to coil springs...now this...
Any advice on the 4WD problem? I think this might send him edge? hahaha

Answer
Land Rover Discoveries are always in 4 wheel drive.  What exactly do you think is wrong?

Is it that the transfer case shift lever won't move?  To shift to low range?  If so, those linkages often rust from disuse and they require spraying with penetrating oil and working free by a service person and a workshop lift.  Sometimes they have not been moved in years and they just freeze tight.