4 wheel drive won't lock up,the transfer case will engauge but 4 wheel drive won't work. There was a vaccum line that was broken from the front axle to the tranny which i fixed but still doesn't work . Before it stopped working it would take a long time to engauge and when i disengauge it would unlock very hard.
Does any body have any thoughts to this problem, Is it maybe a sensor

Your profile says 99 1500; right?

OK so the vacuum wasn't working too well initially, then quit entirely. I'd suspect the vacuum system for the front axle, and check there first. Make sure the hoses are in good condition, don't have any kinks or flat spots, and are connected properly. Trace the system back all the way from the axle to where it terminates.

there is a shift fork in the axle that could be jamming up due to a number of things.could be a vacume prob or a prob with the fork itself. hows fluid in axle? if you take off cover you can check for metal pieces for a true diognosis. won't hurt to change fluid anyways!!!

[QUOTE=fredjacksonsan]Your profile says 99 1500; right?

OK so the vacuum wasn't working too well initially, then quit entirely. I'd suspect the vacuum system for the front axle, and check there first. Make sure the hoses are in good condition, don't have any kinks or flat spots, and are connected properly. Trace the system back all the way from the axle to where it terminates.[/QUOTE

Thanks for your reply Fred.
I do believe that it is a wiring problem off the sensor on the axle going back into the main wiring harness . I have went though it with an o meter to find no voltage ,Vaccum lines seem to be fine, I will let you know and thanks for your time.

Dale

Thanks for your reply Fred.
I do believe that it is a wiring problem off the sensor on the axle going back into the main wiring harness . I have went though it with an o meter to find no voltage ,Vaccum lines seem to be fine, I will let you know and thanks for your time.

Dale

So no voltage to the actuator, hmmmm might be a problem there. :) Mudder does have a point though, so opening it up would be a good idea.

all the wiring dose is turn on the light on the dash, even if there is a problem with the wiring, it will have no effect on the locking and unlocking of the CAD unit.
go here, http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm
there is a diagram of how the CAD (central axle disconnect) unit should be hooked up, and how it works.
hope this helps ya out some,
Keith

Keith, great resource thanks. I done been edumacated.

So no voltage to the actuator, hmmmm might be a problem there. :) Mudder does have a point though, so opening it up would be a good idea.

I thank you guy's for your help , I did pull the cover off and the forks and interal parts are fine. So what i did was locked up the interal gears and put it back together , very temporary but it did stay in gauged . The 4x4 light doesn't come on so on i'am guessing that maybe the actuator itself . As there is lots of vaccum out of the black line going into the housing and the housing canister seems fine . But one question i do have this canister doesn't act like a one way valve does it ? For some reason i think it is the actuator sensor but it most certainly isn't interal.

Like i said thanks alot guy's and if you have any other ideas . I will be sure to let you know the out come .
Dale

all the wiring dose is turn on the light on the dash, even if there is a problem with the wiring, it will have no effect on the locking and unlocking of the CAD unit.
go here, http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm
there is a diagram of how the CAD (central axle disconnect) unit should be hooked up, and how it works.
hope this helps ya out some,
Keith

Thanks Keith , I'm printing out this link you sent as it should help solve this delema .

Thank you .
Dale

After reading on the link that ScoutinKeith sent, it may be the actuator, since those go bad often.....

After reading on the link that ScoutinKeith sent, it may be the actuator, since those go bad often.....

4x4 not locking up,problem solved

Hey Guy's
To Fred , Keith , Mudder
Once again i would like to take the time to thank you gentlemen . I thought it's only proper to let you guys know what the problem was .The Vaccum control motor was finished as the only thing i can think the diafram must have a hole or a crack in it . There for wasn't locking up the front end.

Thanks
Dale

glad you found prob. i'll check that first if mine stops working!