This will happen when you lock your centre diff (it may happen to a lesser degree as you wind the lock off) because of the diff binding. Remember that when you lock the centre diff, it is trying to keep the front and rear wheels going at the same pace. So when you are turning, your front wheels travel a shorter distance then your rear wheels, therefore causing the centre diff to bind up. You should not have the diff in "lock" position on tarmac anyway, it puts a lot of stress on the centre. Lock is really designed for gravel and loose surfaces.

Hope this helps,

Darren

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