yup. Normal. Your car will sound like something is broken if you try a tight turn at 50/50 locked.

Its the DCCD unit in the gearbox making that noise. It has locked the front and rear axles together. When you make a tight turn the front and rear axles will rotate at different speeds which causes the center diff when locked to clunk and groan. It will try to keep the axles locked together and will cause one of the inside wheels on the turn to skip as well.

99.9% of the time I leave my DCCD on full rear. Unlocked.

__________________
RS Liberty - Because WRX's are only good for parts...