Can anyone explain the mechanics of this to me? This is a 98 Truck. I have vacuum going to each vac line (depending on switch position) on the diff but it never engages. I put a vac gauge on the diff itself and one side I can pull vacuum and one side I can’t. I assume this is where the issue lies but I don’t understand how it works to know for sure.
2 valves to control the vacuum. When they are powered one let's vacuum go to the diaphragm and the other vents the opposite side of the diaphragm. When the power is removed they swap functions. I have a PDF of the 4x4 system if you like. Not identical to my s110p but gives general idea how it works. The actuator on the transmission selects power to the front driveshaft and the diff one unloads the front axles from the driveshaft.
And I have vacuum at the hoses that connect to front diff. One or the other depending on 4wd switch position. What I need to understand is the part that is in the differential that connects the axle to the front driveshaft to make it work. The front diff is my guess on where the problem lies.
The piece that slides over the axle shaft to connect the inner and outer shaft pieces was corroded and wouldn’t move. Cleaned it up and replaced the seals and it works fine now.
Could you email me the diagram of the 4x4 system that you mentioned above? tsprevite@yahoo.com Thanks in advance
