So here is what I have so far:
1. With Hubs unlocked with 4wd button pressed in (no green light by the way) engine running, driveshaft spins easily by hand. This is BOTH in 2wd high AND 4wd low.
On the firewall, the blue VSV solenoid has 12v power when the 4wd button is pressed and the RED VSV solenoid does NOT when pressed in. Then when I turn the 4wd button OFF this reverses, with the BLUE VSV having no power and the red VSV having power. But all this with no green light on the dash.
There is vacuum to this, it does "suck" when I put my thumb over the vacuum supply hose that is fed from the top of the intake manifold.
I bought a new Blue VSV vacuum solenoid from the dealership part # 88690-89132 and installed it (easy job) and still no change.
Hope to hear back as It is an incredibly nice truck.
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