I was told by the tech at ford that I need to put vacuum on the actuators (4x4 front hubs) in order to properly install them. I have never heard or read this in any manual. Is there any truth or our they trying to get the install. I bought both actuators, new solenoid, and a new check valve. Going to install all tomorrow and finally have a functioning 4wd system

 

Yes this is true the system applies vacuum when the system is off and turns off vacuum when it is on. Ford made it backasswards.

 

So all you would have to do is hook up the vacuum lines, start engine, install actuators.

 

yes and the solenoid thats what turns the system on and off. I'm having problems with my system too, the right side hub is engaged and the left side is trying to, so i'm kinda driving around in 3 wd so to speak cause i need a new actuator

 

So I wont need a special tool. I can get actuator into position, hookup vac lines and assuming truck is in 2wd it will suck in the actuator and allow it to fit into position?

 

The instructions for installing the actuators say to compress the unit (by hand, it's easy). Then place a cap (I got a pack of mixed sizes at the parts store) on the vacuum line fitting on the actuator. If you cap the wrong fitting the actuator won't stay compressed, so it was "me proof". I really don't know why this is necessary. The cap popped off at some time while I was installing my actuator[s], but everything still went together fine.
There is no vacuum applied while you are removing the old parts. Except for the strange instructions requirement to compress/cap the unit during installation, no vacuum will be applied until the engine is started after the work is done. The whole process is easier than it sounds...
Just make sure you have the vehicle securely supported while you work.

 

...the bolts for the actuators are 5/16". I had to dig around to find that tiny socket. The nuts for the steering arm and upper control arm bolts are 21mm. I ended up using a adjustable crescent for that...bigger than my set of sockets/wrenches had. Note to self, buy more tools.

 

I did mine this week-end, and yes you have to let your engine run for a little time before putting your hose back on your actuator. I did not do that and when I got on the road after it was still trying to engage. I've just hook up the hose for couple of minutes and put it back on and everything is fine now ! Hope it help !

 

If you just replace the solenoid do you have to do anything with the vacuum? If the system is working correctly and this is just a preventive measure is there anything else you should check when replacing the solenoid?

 

You can just unplug one of your vacumm lines and start the truck for couple of minute and then plug them back. I don't know if it's really necessary but I don't think it would be bad to do it !
Hope it helps !