4x4 Acuator Question
 

Hey does any one know how many lbs of vacuum it takes to activate the 4x4 actuator? The reason I ask is my seal is going bad between the power steering and vacuum pump and I have the kit to repair but just haven't had the time yet. Anyways yesterday when I went to use 4wd I had none. Thought it could be because of lack of vacuum but it had been working. Also I get no 4x4 light on the dash. Shouldn't the light still come on? Maybe it's the actuator itself. Any ideas on this. I know the seal needs to be done but I'm waiting for a little nicer weather. I really need 4wd with a dually unless I carry a couple thousand lbs. in the bed.

quick down and dirty test, pull the actuator , KOEO, and shift to 4wd, if the fork moves
actuator is fine, , they are prone to corrosion and if they get water inside it could be a exspensive repair
for the light, ground the two teminals and light should illuminate, if not check the cluster bulb

I don't know how much vacuum it takes but the 4x4 light won't come on until the fork in the acuator moves. You might take a look at the acuator to make sure the vacuum line and the wires for the light are hooked up.

Vacuum lines all looked good and wires seem to be good. My guess is actuator. Anyone ever try a 4x4 posi lock 4x4 Posi-Lok Positive Axle Engagement System for Dodge 4x4s

lol Love your status Bryce

im a big fan of keeping things as stock as possible , but this kits looks like a cool idea

I kind of thought the same thing. Just wondering if anyone here has tried it or knows of someone who has

the hillbilly fix is to remove the fork and center the piece where it is suppose to be in 4wd. then tack on each axle so it cant move. it will be in place every time you need it. only down side to this is the tack weld on the axle if you are removing them to put joints in. :hellox:

do a youtube search there is a simple cable attachment to make that will make it manual from the cab. I got all the parts and and extra CAD but have not done it yet.

get a vacume hand pump,goto the actuator one line is to engage the other is to disengage,jack up one front wheel,put vacum on each line,it should (a) hold vacum (b) move shiftfork/collar. The reason for jacking up the wheel is to move it a little to make sure the splines on the collar&axle engage.The light switch is at the actuator,so when itgoes into 4wd then makes contact. Does the heater control work,If that works right I'd think the 4wd should. Get a vacum gage & check the vacum atthe pump,mine leaked and every thing worked.The valve for the 4wd is on top of transfer case.hope thishelps:tu:

Yes heater controls work. That's why I was wondering how many lbs of vacuum it took to activate the actuator. I know the heater controls work off vacuum also but thought maybe it took more for the actuator. I think the actuator just went out. Plain and simple. I think I'm going to look into that posi lock some more. I kind of like that idea. I really like the idea of having a 2 low also. That could come in very handy with backing some heavy trailers on hard surfaces:tu:

Hello, I am new to the forum although I have looked here several times as a non member for information.

As far as your 4x4 actuator, I would remove the actuator and remove the snap rings that hold the shift fork on the shaft. You can then slide the fork to the other side of the actuator and reinstall the snap ring. This will permanently lock the axle in 4x4. It will not lock the truck into 4x4 as the transfer case will not drive the front drive shaft. Trucks made after 2002 do not have the front disconnect and operate this way anyway. The only real drawback is your 4x4 light will no longer work. The good thing is you can always put it back to stock with little to no trouble.

The the 4x4 vacuum actuator on is a known trouble spot. Unfortunately you dont often know that it is a problem till you are stuck and trying to figure out why your truck will not go into 4wheel drive.

As far as repairing it back to stock, I would climb down by the transfercase and check for vacuum at the plug. If you have have vacuum there, shift into 4x4 and see if you get vacuum down at the actuator. If you do not have vacuum there or it doesnt switch ports when you move the shift actuator, I would say you have a bad vacuum switch on the transfer case. If you do get vacuum there and it switches when moving from 2wheel to 4wheel, and it still does not move the shifter, then you most likely have a bad actuator. Also make sure check the bulb. You can jump the plug on the actuator to see if the bulb lights up.

I hope this helps.

Thanks for your reply. Just not sure if that's the route I want to take either. Great idea though. I'm really liking the idea of the posi lock since I found it. I know one thing for sure! I need 4wd back driving this dually in this crap weather lately is a real adventure. I was seriously thinking of taking my Smarty and setting my truck to half power. :scare2: Yeah I know!!!