Chevy S10 4wd Vacuum Actuator Repair Ring

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This is a set of printed parts to repair the 4wd vacuum actuator on S10s for locking the front differential. The OEM part lasted for years but finally gave out. Every aftermarket part I've replaced it with sucks. I only get about a year or so and the rubber starts to deteriorate. I finally had enough and designed some parts to make this actuator serviceable. It can be rebuilt with a piece of thin rubber/silicone/nitrile of your choice (more on this later). There are 3 main components though you really only need 2 of them. 2 large clamping rings and the spring plate (this part is optional). I started by disassembling the old actuator by prying off the aluminum crimped ring with a screw driver and cutting pliers. Once removed unscrew the cable holder from the aluminum plate to remove the old worn out rubber. Take your new material and mark the center. Punch or cut a hole to allow the bolt to fit through. I have not decided what type of material to use permanently. Right now I have a piece of bicycle tire inner tube for testing. For assembly you may need help from a friend or some clamps as you will need to make adjustments to center the new "boot" and measure the height. What I mean by this is how high the top of the boot sits from the housing. It must be high enough to connect to the cable without putting tension on it. Remember, when vacuum is applied during 4wd the actuator will suck the boot in and pull on the cable. When 4wd is off, the spring helps release the cable back to its normal position. I did not measure this height YET...but will edit this when I do get the correct height. Just make sure the cable has slack when the actuator is reinstalled. One of the rings has a step in it, this lets the actuator housing sit flush in it. Your new "boot" will be sandwiched between the stepped ring and backup ring. The holes are sized to thread an M3 screw snug with a length of at least 20mm to fit a nut on the end. A little more if you want washers. Just using screws by themselves will not completely seal the rubber between the clamping rings. I tried it and it does leak slightly. Hence the addition of nuts/washers. Now it is 100% airtight. For those who choose to print the spring plate, be aware you will possibly need to change the length of the bolt to accommodate the thickness of the new plate. The only advantage with this plate is the pocket which the spring can sit in without it moving around during operation of the unit or assembly. Hope you find this thing useful. If something is not clear feel free to ask questions. Or leave comments. Enjoy