4x4 problems

[lksdrinker]

New guy to the site with a couple of questions. I've been lurking for a while now whenever I was doing some repairs....most recently when doing a heater core, radiator flush, blower motor repair, spark plugs, etc.

I've got a 92 Explorer and cannot diagnose my 4x4 problem. Nothing happens when either button is pressed on the dash. So I went to the rear hatch and pulled the two harnesses from the 4x4 module and after pressing the reset button the LED flashed 4 times and stopped. Plugged the wire harnesses back in and then I took apart the dash switch. The switch is currently connected but the front panel/buttons are not. If I use a test probe light I can get the switch to work...ie there are three contacts that when hit will lit up 4x4 high, low, or just the solid light on both the dashboard and the switch. But when I get those to light up I cannot hear any relays clicking anywhere.

In any event pressing the buttons will not make anything happen...no lights on the dash or switch and no clicking relays anywhere.

So I cant figure out what to look at next? Is there a better way for me to test my switch...can I measure resistance across certain terminals with a multimeter or anything like that? Are there any relays near the 4x4 module that I can try swapping out? Should I just look at doing the shift motor rebuild to see if that helps?

 

[Mettler]

Its not electrical dude. Its time to pull and re-build the transfercase shifter motor. There is a how-to on here that takes you through step by step, with picks. I just did it cause mine was doing the same thing. Hint, though he shows pulling the whole motor apart, you dont need to go that far, unless you want to. Just get the motor off the truck and pop the three torx screws out and fix whats broken. And belive me, you'll definatly see something broken. After that, your 4x4 will work better than you've ever known it. Btw, the fix calls for a small piece of rubber tubing. I used 1/4 inch clear vinyl tubing that I used for my dirtbike carburator.

Good luck. Heres the link
http://www.explorerforum.com/forums/showthread.php?t=123542

 

[lksdrinker]

It was the shift motor! Pulled that thing off and tore it down.....sure enough there was some remnants of a destroyed bushing floating around in there and nothing left of it on the stop/screw. So I popped a piece of hose on there and cleaned up all the contacts. Re-installed the shift motor and voila I get a reaction from the buttons on the dash. Everything seems to work now; both low and high engage.

Now my only problem is figuring out if my automatic hubs actually work. I've never had the 4x4 working in this truck so Im not too sure how it should feel. But I'm pretty sure at least one of my hubs is not engaging.....feels 'chattery' and not very smooth. So I'm gonna start poking around there and see whats up with those hubs.

I've had the hubs apart in the past and believe I might have forgotten to re-install the plastic thrushwashers (only on one side of the truck). Is that most likely my problem or should I be looking at something else as well?

 

[Blacksheep Josh]

I think you should look at the 4x4 Troubeshooting Thread and go from there.

 

[lksdrinker]

I've been checking the 4x4 troubleshooting thread....which helped me fix the shift motor!

I confirmed that my hubs are engaging by jacking up the front end one wheel at a time, spinning the front driveshaft which eventually locks up the wheel and gets it turning as well. Both sides tested the same, but didnt exactly feel smooth once engaged. Felt a bit chattery. Anyway when driving everything seems to engage, but again doesnt exactly feel smooth once its engaged and they dont disengage smoothly at all. It seems that they will not always disengage unless I travel in reverse for a while (sometimes just a few feet and sometimes much further).

Am I just overreacting to how this feels when driving? Should everything disengage without having to travel in reverse first? I've never actually had the 4x4 working correctly in this truck and wonder if maybe this is just how everything is supposed to work? Should I pull the hubs and make sure everything is clean and where it belongs....or just let it be the way it is?

 

[Mettler]

U-joints. most likely front axle and front shaft, ( tc to front diff)