I'm just about done reassembling an 04' S10 crew cab 1/2 basket case project I took over from my brother. It was in pieces down to the frame from the firewall forward for almost 3 years. The truck is back on its feet and running again though not on the public roads yet...I've been taking test drives on local small roads to make sure nothing falls off, launches, catches fire, etc. and that it kinda steers ok, and stops...details details.
The problem that has me stumped and asking all of you for help is the four-wheel drive actuator pod is operating backwards. When two wheel High range is selected on the dashboard, vacuum is being supplied to the actuator pod which retracts and pulls on the cable to engage the differential. When I select the 4-wheel High mode, vacuum to the actuator pod is shut off and the cable is released. Backasswards.
Of the many S10 vac /4WD problems I found searching forums for a solution, I didn't find any posts/threads with the backward operation problem.
I have read about everything I can find and still have no idea why the actuator pod would get vac in 2 wheel drive and no vac at the pod in 4WD. Not having worked on this type of vac actuation before doesn't help. The vac switch (GM), actuator cable, and lines are new.I have double checked that the vac lines are properly connected to the ports on the vac switch at the T-case.
I must have assembled something wrong because the four-wheel drive was working as designed before he took it apart. Where in the pathway from dash switch to the actuator could an incorrect assembly cause the "backwardness"?
I sure would appreciate any info or ideas on solving this... Thanks in advance.