I just got a 99 Ford f150 with the 4.6. I am having problems getting the four wheel drive to engage. I turn the **** on the dash and the lights come on for four high and for four low. I have a 00 four by four and it works fine, so I know how to work it. In the 99 I can hear the transfer case engaging and everything clicks just fine just like it's going into fourwheel drive, but the front end is not pulling. The front drive shaft is turning but still the front end is not engaged. Does anyone know where to start looking to see what the problem may be?

 

Hello Richard,
On the front axle driver side is a vacuum actuated Actuator that engages the front drive solid.
Check out that operation for a fault.
Even if the dash lights come on, the system can't tell if the Actuator works but the driver knows it.
Good luck.

 

Thank you, I will take a look at it and see if that might be my trouble.

 

there are two vacuum hoses to the axle. One to engage the 4 x 4 rod, the other to pull it back out (off). You can take the hoses off and turn the dash **** on- off and see if you have vacuum on both sides. If yes, then the engagement mechanism is stuck. Spray with penetrant and work it back and forth. If no vacuum, look at the firewall in front of the steering wheel for two soldenoids and vacuum hose supply, and two to the axle.

 

Thanks guys. I believe it was just stuck. I got it working by lubing it up but i think its been stuck for so long that it may take it a while to free up completely. I got it working and then it quite again and then started working again so hopefully it just needs to free up some more.