Front Differential 1999 Chevy Silverado

I have a Chevrolet Silverado 1500 1999 1/2 ton 5.3L automatic 4WD.Question:  know I have a 1999 Chevy 1500 ls 5.3L 4wd, but I wonder if it normal and my front driveshaft spin even in 2wd. the transfer case has re-munufactured were totally with half box update and I change the electric motor transfer case, front axle actuator, switch to selection at dash bord. Could you please enlighten me on this problem. After can you give a quotation  for ship a complete front axle for my truck.Answer:  Yes on many of the NV246 transfer cases the clutch pak has enough pressure on it even in 4x2 position that the front shaft will always spin, this is normal.We can provide a front differential assembly your cost is $862.50 exchange with a $250 core charge plus the freight . We would need the ratio or a Vin# to figure it out, below you can see a list of units that are available. Its important to match the current differential ratio, front and rear need to be the same.