My 4X4 in not engaging can we fix it?

There is a vacuum motor actuator on the front differential that engages it. There are two vacuum hoses that run from a vacuum solenoid on the passenger side fender.

For the front differential to engage, enough vacuum has to be supplied to the actuator motor. If it is too weak, it won't full engage.

I attached a pic below. It shows the vacuum hoses (2), the solenoid, and the vacuum motor on the front differential. Check to make sure there are no leaks anywhere in that system.

If no leaks are found, confirm vacuum is being supplied to the vacuum motor. If it is, then you will need to remove the vacuum motor. See pic 1 for component identification. I highlighted the ones in question.

Number 4 is the vacuum solenoid

number 5 is the upper vacuum line

number 6 is the lower vacuum line

number 9 is the vacuum actuator motor

If you find the actuator is bad, you need to remove the differential cover. Here are the directions once the cover is removed:

4. Unseat the clutch shaft rod boot.

5. Remove the snap ring.

6. Disconnect the front axle actuator motor assembly.
(1)Fully extend the front axle actuator motor shaft.
(2)Plug the vacuum ports.
(3)Pull the front axle actuator motor assembly out.
(4)Push the front axle actuator motor assembly away, disconnecting the lever from the slot in the actuator motor shaft.

7. Remove the front axle actuator motor assembly and boot.
(1)Remove the boot.
(2)Remove the front axle actuator motor assembly.

Check out the diagrams (Below). Please let us know what happens.

Happy to help. If you get a chance, let me know what you find. Remember, it could be a vacuum hose leaking and not applying enough vacuum to fully operate the vacuum motor.

Take care,

Joe