Differential Left Case
WARNING: This page is about a different car, the 2006 Suzuki XL-7. However, it is still accessible from the selected car via links, so may be relevant.
Check clutch for smooth movement by pushing plate of axle lock clutch fitted to differential left case.
Also, check return spring (1) for settling.
Check teeth of axle lock clutch (2) fitted to differential left case (1) for wear, damage, and any other abnormal condition.