Attention: TDR Forum Junkies 
I've been getting the 4WD SERV light about once a year since new. It usually came on during a road trip and it always went away after a few minutes. Back around the first of the year it came on and stayed on. 4wd would not engage with the light on. Code reader showed C1464 and C147B. I replaced the front axle actuator (SECOS part) and all was good. A month later I drove thru a flooded road with about 10" of water and the 4WD SERV came back. SECOS part was clearly flooded and leaking water from seam. Replaced it again with a Dorman part that never worked right. Replaced it again with another Dorman part and a month later it still works.
Attached is a photo of the OEM part that shows a burned circuit board. Not any water in it that I coud see. I didn't open the SECO or Dorman parts because I returned them under warranty (Amazon and O'Reillys). The case seal is just a little sloppy silicone!
Actuator takes 5 minutes to swap out. 4 10mm bolts and a plug. Point the truck down hill and elevate the right side about a foot and you will only lose about a spoon of gear oil.
Attached is a photo of the OEM part that shows a burned circuit board. Not any water in it that I coud see. I didn't open the SECO or Dorman parts because I returned them under warranty (Amazon and O'Reillys). The case seal is just a little sloppy silicone!
Actuator takes 5 minutes to swap out. 4 10mm bolts and a plug. Point the truck down hill and elevate the right side about a foot and you will only lose about a spoon of gear oil.
