I want to start of buy saying there is a load of great information in this forum. It's helped me with some transmission problems and some great information on the 4wd system. However I have a problem.

My front CAD isn't locking in place. I've been working on this off and on for close to 8 months or more. I replaced the vacuum switch on the transfer case as it was locked up. I recently just got the vacuum actuator up front from a salvage yard. I changed them today. It's still not working. However the new one moves so much more freely than the one I took off. It felt kind of "chunky" when moving the fork side to side.

I remember reading some where that vacuum should be on the driver side line up front when the transfer case is in 2wd. When switching to 4wd it should switch the vacuum to the passenger side line. I have vacuum on the 2wd but not on the 4wd. I confirmed the actuator is working fine by switching the lines around. I put the 2wd line on the 4wd side of the actuator. It engaged instantly.

I removed the rubber lines up front and they are not clogged or collapsed. I removed the rubber lines from the rear and no air is passing through the steel line. As you guys know these lines run above everything and can not be easily replaced.

I attempted to run some welding wire through the steel line today only to not make the first bend. It just stops. Do you guys know of anything to un-clog these lines? Air from a compressor only pushes back. On a side note what the heck is in there to even get clogged?

If no one has any ideas that has worked for them I will have to run a new line. My plan for this is to keep the lines attached up front. Keep the lines attached to the vacuum switch on the transfer case. Pull the line off that goes to the vacuum canister by the transfer case off. Next start the truck and put it in 4wd. From here I will pull the remaining 3 lines off one at a time so I don't mix them up. One should be giving vacuum from the metal line from the intake manifold. One should be nothing as it will be the 2wd side of the front actuator. The other should be providing vacuum on the rubber hose coming from the vacuum switch on the transfer case. I can then extend this line up front to the 4wd side of the actuator.

That is more work than I would want to do if I can simply unclog the line. So anything anyone can provide on this would be more than helpful. Otherwise looks like I'll be doing what I mentioned above, hope there is vacuum on the line that should be the 4wd, and extend it. If I do that and two lines have no vacuum I'm completely at a lost. This should not even be a possibility since vacuum does exist and it's a new transfer case switch. Let's hope!!!

Either way having this documented may help someone else in the future.

 

I would say just buy some replacement hose rubber line or steel brake line both can be under $5 and only take 2mins to route it to where you need.

 

I believe this is what I'll be doing shortly. I was hoping someone had a genius idea to safe me the aggravation and trip to town. Not to mention I like to keep things stock when it comes to functionality. I'll post up the results when I get done.

 

Jus to make an update on this. I found the 4wd line and it did have vacuum off of the switch. Ran some new line through the frame rail and away from the exhaust. It works flawless every time. Such a good feeling. However now winter is over so it's time to find some mud to check it out!!!