There is no universal safe answer. A fault affecting only mode selection differs from a transfer case with low lubricant, damaged internal parts, or severe binding. Continuing to drive may worsen damage or lead to loss of drive.
Switching to two-wheel drive does not necessarily isolate a damaged transfer case because components may still rotate. Do not assume a mode change makes the vehicle safe.
Contact Certified Transmission at 2112 West Broadway in Council Bluffs for guidance. If you notice grinding, substantial leakage, binding, or unreliable movement, stop driving and arrange assistance.