I seem to have a problem with my 2000 F150 4x4 Lariat Supercab. I'll flip the switch on my on the fly and the indicator light turns on but the four wheel drive isnt engaging. A friend told me it could be a relay of some kind, another suggestion was the axle. Granny low does not engage either. Any suggestions?
I appreciate any advice.

 

well on my 97 it was the vacuum seal, but know on my 06 its not enjaging i think i broke it though

 

Check your vacuum switch. It will be down underneath the pass. side on the axle. Take the tubes off and see if you have vacuum on both. One tube should have it while it is engaged and the other shouldn't and vise versa. If that checks out ok I would lean toward the shift fork inside the front axle. That's what mine was.

 

You should hear the shift motor on thr transfer case engage, a whirring sound , as the light goes on. These motors do stick from non use. If you don'y hear it, then have someonr turn the switch on the dash from 2wd to 4wd high while you tap on the shift motor with a hammer. Do this with the key on, but engine off. Do not hammer on it hard, as it can crack the case. If you hear the sound of the motor engaging, then check for vacuum at the hubs and check the 2 valves on the pass inner fender to see if they are functioning.

Barry

03 F-150 4x4 reg cab
( Ford parts man )

 

Ok, I found a hose connected to the front axle, I follow it up to the engine bay, but the hose goes nowhere. Do I need to plug the hose in order to engage the vacuum, or has the tube fallen off from somewhere. It is a black hose, and I don't think that it fell off from somewhere because it is zip tied to another un-moveable object.

 

That may be just a vent hose.

 

Yeah, thanks for the help, I ended up figuring it out. It ended up being the piston that engages the vacuum pump. It had not been used in a while, and I had to loosen up the piston by compressing it. (I have a 97 Ford F-150). If I some how find out how to post pictures, then I will prvide a picture of what piston I am talking about. But it is located on the front axle right next to the transfer case. This is a great site and a great forum.

 

i had a the same problem, that piston was froze up. even after using a screwdriver to free it it was still to stiff for the vaccumm to move it. a temp fix, is to put a hose clamp around it, and lock it in place. im still waiting to install my http://cgi.ebay.com/ebaymotors/ws/eB....cWON.m313.lVI

 

It turned out to be the shift motor was stuck from non use. I got under there and worked it back and forth with a screwdriver, then WD'd it and it now works great. Really appreciate the help. This is a wonderful website.
thanks again.