Verify you are getting vacuum at the cad when you put it in four high. Should be vacuum on the outboard port in 2wd, inboard port in 4wd. Don't have to have the truck in gear to test, but, it does need to be running.

 

ok : problem to run your test Hey you is , the truck does not go on 4H . that is the lever stops on 2H. and does not go past that , some days ago one of the boys sugested checking the lever on the transfer case to see if it has moved from position and it has not i took it appart anyway loosing the bolt and asked my son to go on top and hold it on 4L. and it was the same no change discarting the posibility of the lever just not going far enough to engage 4h. let me know what else we can try , thanks

 

thanks guys for all your help ,any other ideas brfore concluding that the transfercase is bad ? what i think it happend is that something came out of line like the sequence or a particular selenoid or sensor is just not reading leaving the transfercase on limbo .

 

There is very little inside the transfer case that will prevent it from engaging 4 high without any other symptoms. It is possible that the shift detent plunger or vacuum actuator are binding up. You can remove them and see if you can shift into 4 high.

 

Jr mechanic the shift detent plunger or vacuum actuator where is this located ? vacuum actuator where is this located ? thanks

 

On the transfer case. Vacuum lines go to the switch, should be right above where the linkage physically connects to the t-case.

 

man I 've been busy , iwill get under the truck tomorrow and check that out , however would that stuff shift detent plunger or vacuum actuator, prevent it from going into 4H. and allow the 4L. to go in with no trouble at all ?

 

Maybe.....

You need to verify if you are getting vacuum at the cad when you put the t-case in 4hi. If I haven't used 4x4 for a while, mine is pretty lazy about engaging. But, if I use it even once a week, it engages almost immediately.

 

no, stop, wait - don't mislead him. his TCASE won't shift into 4hi. don't go chasing after the cad when the t-case won't shift properly.

i don't know what is wrong, but if its not the shifter or shifter linkage binding up, then its something inside the tcase.

did you disconnect the shift rod from the t-case and try to shift the t-case lever manually? its a little green press-on plastic connector that just pops off. if you haven't tried that yet, do so.

the vac switch can be seen in the 3rd pic. i doubt that that little push ball has anything to do with the problem.
https://dodgeforum.com/forum/2nd-gen...31-np231d.html

 

Alright guys promise me you all not, I say (NOT) to laugh . found the problem its 12:35 am and I just had to tell you . last week I removed the rug to be replaced and received the new one shortly after installed the new rug man a perfect job however did not noticed that one of the bolts holding the shifter plastic oval enclosure dropped under the shifter , I thought that it was just a single sheet of metal separating the inside of the truck and the outside of the truck well is not where that shifter plays up and down there is a double pocket the bolt dropped in and could not go anywhere it is totally enclosed so when the shifter goes backwards the bolt would not permit it to go past neutral . man I was starting to worry real bad , thank you all for your combine experince and the patience to deal with all of these , thanks again really appresiate all your time