I have a 1997 F-150 with a V8 4.6L W that will not engage the high side of the 4X4. I am pretty mechanically inclined but have never worked on 4 wheel drive systems. Any help or suggestions would be appreciated. I am leaning toward an actuator or the vacuum solenoid but do not know where or how to test these. Thank you.

 

I have the same thing on my 2000 7700 series. But the light isn't even coming on for me. Not fun...

 

that happened to me once ....

 

Just recently picked up a 97 f150. upon purchasing i clicked into 4wheel drive. heard an electronic engagement noise and the 4x4 light on the dash lit up. Just yesterday i had the truck up on the jack and wanted to make sure the four wheel drive did indeed work. switched the switch, heard the noise, light came on.... but no 4x4 action. neither high or low range would engage. both lights would come on but no engagement. thinking potentially electric shift motor?