I recently swapped a 2003 engine with accessories and harness into a 2006 silverado 1500, along with a new transmission and transfer case. I am still using the 2006 pcm, tac module, and body wiring (would have kept the 03 pcm but the gas gauge worked backwards and the pcms had a different service number). I used the 06 t-case control module (encoder motor). The truck is running fine and it drives well but the only issues are the 4wd and the cruise control do not work. "service 4wd" is displayed on the DIC and I checked the codes. C0359, and C0379 and a couple of others that come and go when checked and cleared. The push-button light is displayed as 2wd and when pushing 4hi or 4lo it sounds like the t-case is shifting but the front actuator on the axle is not and the light will just flash. The truck will shift into low-range but it is still only in 2wd and the light wont stop flashing. Also the cruise control does not work at all. Not sure if it is related at all but after the swap the oil pressure gauge will make a full sweep when the key is cycled but then stay pegged and when the oil pressure sending unit is unplugged the gauge drops to 0...Any help would be greatly appreciated, thanks in advance.