Removing the front driveshaft will relieve the strain you're putting on your differentials, transfercase and driveshafts until you get the transfercase fluid changed.
I'd hate to know how much damage to expect from 3 months of driving normal road conditions in AWD.
It's likely the noise you're hearing is the front differential getting against the snubber...a bracket with a rubber biscuit to keep the differentail from twisting too much under off-road conditions.