The 242 transfer case shifter pushes against a spring which pushes the gear- that changes it into/out of 4wd
so if there's any torque difference on the axles front/rear - the gear won't engage or disengage.
so 1st try putting it in neutral while slightly rolling (2-4 mph) and try the into/out of 4wd
or stop and back up a bit.
also check tire pressures - a low tire will cause extra torque on 1 axle vs the other.
you can still drive it if it's stuck in 4wd Full time - but don't try if it's stuck in Part time - it'll blow the transfer case.
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2005 CRD
stuffSkeptic quod gratis asseritur, gratis negatur