I have a 2003 f150 4x4 and my front driveshaft will not disengage when in 2wd. It always spins. All the 4wd works fine ive tested it multiple times this winter. Goes in and out of 4wd fine no issues. The problem is the front drivshaft will not disengage when in 2wd.

What would cause the front driveshaft at the transfer case to stay engaged but the 4wd to be unlocked down at the differential?

 

so what your sayin is the front driveshaft is spinning while your driving but your halfshafts are not spinning at the same time or are your halfshafts spinning also

 

The halfshafts are always going to spin, because it doesn't have IWE's or locking hubs. The axle lock is in the diff.

 

lmfao.

 

check the front diff actuator, when u engaged the 4wd the actuator engages the front differential and its probly stuck in the 4wd position. Also check the solinoids behind the battery those are what engages and disengaged the front axle when u select 2wd or 4wd hi or low. So basicly the transfer case is disengaging the power to the front axle but the drive shaft is still spinning. so i would check the 4wd actuator, the solinoids and the vacumm lines for leaks. i hope this makes sense, let us know a update and if u have more questions

 

Ok I will check these tonight after work. Thanks guys and will keep you posted.

 

The halfshaft always spin on these year trucks regardlesss they never unlock like the newer trucks. The problem is the front driveshaft is still spinning when in 2wd and its not supposed to be.

 

Possible electric motor problem on your transfer case??? Here's a manual one if you want to convert it:

http://theshiftster.com/

----DirtySCREW

 

Four things come to mind.
1 - A vacuum leak in the disengage system vacuum lines.
2 - A faulty disengage solenoid or its electrical system.
3 - A stuck actuator motor or a leak in its diaphragm.
4 - A stuck lockup collar in the front axle.

Apply vacuum to the disengage side of the actuator motor. Does the lever move and does it unlock the front axle? If it does then you have either 1 or 2 as the problem.

 

yeah i was just tryin to figure out what you were sayin i couldnt really understand

 

JMC, I am having the same problem and would like to know which one is the disengage side of the actuator motor. I am going to test it for proper functioning tomorrow.

I wonder if the vacuum here is a burst or a continuous supply. Because I am not having any vacuum at neither 2wd nor 4wd.

If vacuum is the problem which lines should I checked beside these two going all the way to the solenoids behind the battery.

I am having two codes right now. 171 and 174, both banks A and B lean. Based on past experiences this is a vacuum problem since I fixed it the first time finding and changing some lines behind the engine close to the firewall. But today after another search for leaks couldn't find any, and the engine noise won't help either.

Any insight will be helpful.

 

I got a 2001 f 150. And the driveshaft didn't disengage. One of the vaccum lines was broken.. You should be able to turn the driveshaft by hand when in 2 wheel drive

 

My 2001 was doin the same and it was one of the vaccum hoses broken.. You should be able to spin the driveshaft by hand