I drive a six-year-old 4x4 sport utility vehicle (SUV). Recently, I began to experience something I would describe as stiffness or a reluctance to move while negotiating tight turns. This symptom is most noticeable at low speed. The car would even come to a stop at times unless I accelerate hard. It seems fine when travelling in a straight line though. What could be the cause of the problem?

Perhaps the first thing you should do is inspect the tyres. Do a visual check at least and make sure they are properly inflated.

The problem may be more complicated, though. Since your SUV is a 4x4, there is a possibility that the drivetrain is faulty.

In all four-wheel-drive vehicles, a centre differential apportions torque between the front and rear wheels while allowing them to rotate at different speeds, which is necessary in turns.

When this torque-splitting device fails, you could either lose drive to one axle or it could completely seize.

A "locked" centre differential will resist any front-to-rear torque and speed variance, resulting in sluggish motion, especially in tight turns. It would feel like a regular two-wheel-drive vehicle bogged down in mud.

Centre differentials may not be serviceable and you may end up having to replace the whole unit.

Unfortunately, this is usually a costly exercise.

Shreejit Changaroth