2nd gen explorer 4wd doesnt engage

[robbiegz33]

Ok so i took the truck to a mechanic for the 4wd. at first he thought the 4wd motor needed to be replaced then came to me and said it wasnt getting power so i needed to replace the GEM module. I did that and still no luck...I lifted the truck and the front driveshaft locks when in 4wd auto but when i spin the front tire the other does nothing. and when i spin the other side the opposite does nothing as well. my 4wd low engages and works. but nothing with 4wd auto. does anyone have any suggestions on a frequent problem or maybe what i can check next?

 

[robbiegz33]

by the way its a 96 ford explorer eddie bauer 4.0L with 2wd 4wd auto and 4wd low

 

[Glen4X4]

Do you have the ignition turned over when you try the front end test? Because the front axle uses vacuum from the engine to lock both axle shafts together and can only accurately be tested if the ignition is turned over.

 

[robbiegz33]

ignition turned over lifted put it to neutral hold the brake and switch to 4wd auto then put it back in park and left it idling in park.

 

[Glen4X4]

Ok, just making sure....then sounds like you have vacuum problems in the lines or the actuator has gone bad. Just to note on these trucks you don't need to put the trans in neutral when switching from 2hi to 4auto or vise versa.

 

[robbiegz33]

so i should check the vacuum lines into the front axle? where is the actuator located? thanks for your help....

 

[Glen4X4]

Yes, make sure the vacuum lines aren't cracked or broken or have come disconnected. When you crawl under the truck on the passenger side on the right side of the pumpkin you will see a little box with a little pan on it above that you will see the actuator.

 

[robbiegz33]

i appreciate it man. i'm going to check the vac lines and if not that then the actuator. i'll let you know how it turns out.