4x4 not working when i shift it in 4x4 auto trans

If the actuator is not working and you need to engage your 4x4 to get home, you can manually lock in your 4x4 system using the front axle's manual locking hubs (assuming your vehicle has manual locking hubs). Here are the steps to manually lock in your 4x4 system:

1. Locate the manual locking hubs on the front wheels of your vehicle. They are typically located at the center of the wheel hub, and will have a dial or lever that you can turn or pull to engage the hub.
2. Make sure your vehicle is in neutral, with the parking brake engaged.
3. Turn the dial or lever on each manual locking hub to the "lock" position. This will physically engage the front axle, allowing power to be transferred to the front wheels.
4. Engage your 4x4 by shifting the transfer case lever into the appropriate 4x4 mode (4-Hi or 4-Lo).
5. Test your 4x4 by driving slowly in a straight line. If you hear any grinding or feel any vibrations, stop immediately and check your manual locking hubs and 4x4 system.

It's important to note that driving in 4x4 mode on dry pavement can cause damage to your drivetrain, so be sure to disengage your 4x4 system and unlock your manual locking hubs once you're back on solid ground.

ARE THE HUBS LOCKED IN FIRST? FOR YOU HAVE TO LOCK AND UNLOCK THOSE HUBS FROM THE OUTSIDE.. EACH TIME YOU GO INTO 4X4 AND WHEN YOU GO OUT OF 4X4 TO 2 WHEEL..DRIVE. OR YOU DON'T HAVE A FRONT DRIVE SHAFT GOING TO THE FRONT AXLE?? OR ITS BROKEN OR THE TRANSFER CASE IS BAD??

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc ). Key on, engage 4x4 and try to turn the front drive shaft. If it turns it is a problem with the transfer case. If it doesn't it is a front axle engagement problem. I would guess a problem with the vacuum disconnect motor on the front axle ( or vacuum lines from teh solenoids or the solenoids themselves ), but best to verify the test above to know which way to go. Post back a comment after the test.

This is for 4x4 shifter on the floor.
In the front of the truck on the axle there's a plastic cover with 2 10mm bolts remove it and spray down the shifting actuator it operates on vacuum. You might have to pull it in four wheel and check to see if the vacuum pod is engaging the shift lever on the axle. Then again you might have to replace it very easy to do. But I would spray it down with some WD-40 it should work.

hope you can help. I have a 97 Dodge 1500 4x4 with a 5.2 litre and auto trans. After shifting to 4x4 high when you move there is a clicking sound form left front axel

ck frt drive shaft out of trans-fer case is turning if it is ck both hubs on outside of axles auto locking hubs have alot of problems

sounds like the punch solinoid in the front diff

shift into 4wd and move truck a couple of feet.
if light is still off, park truck block the wheels set the park brake jack right front wheel and try to hand spin the wheel if wheel doesn't turn 4x4 is functioning properly but there is a wiring problem use an ohmmeter to check the 4x4 switch wiring fuse and bulb
if wheel turns freely the front axle or transfer case is not engaged
attempt to hand spin the front driveshft if the driveshaft will spin the transfer case is not engaged check the transfer case shift linkage, problem is in linkage or transfer case internals
if the driveshaft will not spin the transfer case is engaged properly
with trnsmission in neutral or park start engine measure vacuum on the two vac lines at front axle shift motor . one line should have approx 20" vacuum. other line should have none
if no vacuum measured look for vac leak or bad vac switch
if both lines have vac look for a bad vac swithc or ruptured cad actuator diaphragm
if one line has 20" +- VAC
move transfer case lever to 2wd measure vac again lines should have swapped vac signals
if no vac switch bad or 4wd shift likage needs adjusting
if yes vac motor bad or stuck or shift fork stuck
remove vac shift motor from the axle attach vac lines to shift motor engage disengage 4wd
does shift motor plunger move at least 1/2 inch
no shift motor bad
yes check axle shift fork and vac motor for binging

Check front axle actuator see if it came unpluged

more than like have a broken axle shaft, un hook the rear drive shaft and put it in 4wd if it wont move then you know you got a broken axle shaft or spider gears broke in the pumpkin