Questions About My 4x4 System

[MVP]

Halleluiah, I got my four wheel drive working!

I went out and started testing the VSV’s as TheDurk had recommended.

Apparently my VSV’s were not changing state. I tried to determine if they are a one part set or individual valves. I couldn’t tell so I tried to pull the electrical wiring connector from the brown VSV. While I was doing that I decided instead to test the VSV vacuum in 4L first. I went back into the truck and noticed that my 4x4 light was on! I shifted back and forth between 2H, 4H and 4L. The light was going on and off as it should. I closed the hood and went for a test drive. I could immediately tell that I was in 4H.

Resurrecting a long dormant thread to say THANKS GUYS for posting your suggestions and efforts. I just fixed my problem with the 4WD light not working and it never getting into 4WD.

Essentially I read this thread about 5 times, went out and started tracing vacuum lines. I had my dad sit in the rig and keep shifting between 2H, 4H and back and forth while I felt each solenoid to check that it was operating.

I had him put it in 4L and Neutral, then back and forth between 4H and 4L. While he was doing that I pulled the vacuum line to the from diff off one of the VSVs and checked for vacuum - there was plenty.

He got out and walk up to see what I was doing, then I hopped into the driver's seat to find the 4WD light was on. Took it out for a spin and it is evident that its engaged and (finally) in 4WD.

Time spent: a couple of hours, mostly reading this thread and researching
Dollars spent: ZERO