Hi Everyone,
I tried engaging 4 wheel drive in my 94 Explorer Sport while at the dump the other day to move more readily through the mud there.
As soon as the automatic hubs locked in the car pulled sharply to the right.
It seemd to me that the left wheel did not lock in. I shut if off and tried it again later when I was on open road. The same thing happened, it pulled sharply to the right as the lockouts engaged and I noticed a strong vibration in the left front wheel.

Is this symptomatic of a broken/bad ujoint? How big a project is this to replace on my own? Special tools needed? Or if I HAD to go to a mechanic what price range would I expect the repair to take?
We are just about to hit winter and I hate to think of driving this thing in a heavy snow without the 4x4 capability. It is squirrley enough on wet pavement when turning corners.

Anybody? How would I test the passenger side joint as well to know if both need replacing?

Thanks.

 

If it weren't engaging due to a broken u-joint, it would be obvious -- the u-joint would be obviously broken. More likely it's a problem with the auto hubs. Might start by cleaning all the excess grease and crud out of the hub.

 

I thought at first that it might be a problem with auto hub but two things made me think otherwise.
1. When I am driving and engage 4x4 the left front wheel gets a lot of vibration.
2. Last few times I used 4x4 I could hear clunking and noise from the front wheels especially when turning at lower speeds.

I believe I needed u-joints anyway but do not know the proper method to test and confirm. So when this problem started I immediately thought it was a bad joint. I would expect a much more dramatic effect if a joint were broken of course but the vibration with 4x4 enabled made me think the shaft when engaged is not centered and causes wobble.

I have a Haynes manual to reference but it is not really great for detail and I have never worked on a 4x4 setup before and do not know what to expect.

 

Are you certain the hubs are engaging? Do you have power to the front wheels? My first reaction to your original post was that one of the front hubs wasn't engaging.

Two parts of a u-joint going bad, other than outright breaking:
1) The bearings disintigrate, which allows the joint to slop around inside the bearing cups.
2) the bearings get rusted to the point that the joint can't rotate within the cups. This will usually be followed shortly by condition 1.

 

When I got home this evening I pulled off the driver side hub and cleaned out the extra muck and put it back together. Unfortunately this did not change things when I test drove it.
When I engage 4 wheel drive the car pulls to the right and I start getting a strong vibration on the right front wheel. Sometimes if I accelerate hard the vibration goes away and the pulling stops.
I assume this to mean that one wheel is engaging and the other not and that would cause the pulling but I do not understand where the vibration would come from. I also assume that the sudden acceleration just gave it enough of a jolt to fully engage the hubs and once the second one engaged it would no longer pull to the side.

I will have to take them completely apart and give them a good inspection/cleaning but the Haynes manual I have does not show exactly the same setup as on my vehicle so I have to be a bit careful in the dissasembly/assembly.

I think my ujoints are on their way out in any event just based on the amount of clunking/grinding when I have 4 wheel drive engaged and am turning a corner. Any recommended method for testing them? Just wiggle and look for play or is there something more?

 

Your auto hubs are screwed you need to change to manual hubs about $300.00
but well worth money it was $1300. for new auto hubs

 

Hey, I am having the exact same problem. But instead of a vibration, I am getting a loud clunking noise. It sounds like the forward drive shaft is wobling. My problem has started to migrate to 2WD now. I will be driving along and all of a sudden, it will start to pull pretty hard to the right. So did you find a fix? Was it the auto hubs? Let me know so I have some idea where to start looking.

 

I have no answers yet, have not had much time recently.
What I believe is happening is that I have two problems.
1. The lockouts are not engaging/disengaging freely.
2. At least one ujoint is getting a little sloppy.

It sounds like one of your lockouts are not fully disengaging and will randomly reconnect so the wheel starts spinning the shaft though the transfer case is not engaged.
I would have thought though that you would only get the heavy pulling if 4x4 was engaged. I guess it is possible that the 4x4 is engaging randomly on you. Watch for the light on the dash going on.
So far my primary questions have gone unanswered. 1. Are my symptoms consistent with what I think the problem to be. 2. How do I test the ujoints correctly. and 3. How difficult are they to replace on this model.

Here is what you can do for some of the testing. Put your Explorer up on jackstands (all four wheels) so that you can see the wheels turn.
When it is not running but in neutral, try turning the front wheels by hand and see if the shaft spins also. It should not spin if the hubs are not enaged.
With it running and 4x4 engaged see if either front wheel spins. One of them should. You should be able to stop that wheel spinning and it will shift power to the other wheel. If the other wheel does not engage but the shaft for it starts spinning then you know that the lockout hub did not engage.

These auto hubs do need cleaning, mine are a mess but I just went and bought some snap ring pliers so I pull out the bearings before cleaning and have not done it yet. I did find while scraping out the majority of the gunk that one of the rubber rings have gone bad, 1/3rd of it came out with the loose muck so that might have been hanging up that hub.

Good luck in your testing.

 

I forgot to tell you that I have a 94 Explorer Limited. I thought it was funny that we both have the same problem.

Well, I pullled off both hubs and cleaned them out. Man there was a lot of "gunk" in them. I could not pull them apart and get in to the innards. But what I did notice was that you have the part that the spline drive shaft goes into and a part that has three tangs on it. I assume this is what "locks" the hubs in. One of my hubs, the part with the tangs would move freely in and out about 1/2" and the otherone was stuck in the what I would assume is the engaged position. I tried tapping on the part to see if it would dislodge, but it did not budge.
So, I broke down and converted to manual locking hubs. It ran me $170 for the Warn hubs and anther $70 for the spindle nut conversion kit and the tool for the nut. All together $240. Very easy to convert, only took about 30 minutes for both sides.

Well, it is fixed! I will have to more than likely change the U joints in the near future, as a preventive measure, But I cant believe that the hub caused that much of a problem.

 

I may end up doing the same thing but money is hellishly tight right now.
Just got married over the summer and Christmas is adding the extra strain on cash.
Do you still have your old hubs? Maybe I can get one working set from both of ours if you want to sell them to me.

Did the problem completely go away? So all that pulling and vibration can really be caused by one screwout hub? I thought it might but in all the questions I have posted nobody answered that question, only said to replace the hubs.

We got a bit of snow today. Will not know how much until I get home as where I work it did not get bad. I shudder to think of trying to get that Explorer out of my steep driveway in the snow without 4x4.

BTW, to pull those hubs apart you need to remove the snap ring down in the bottom of the hub and it should all slide out. I have not done mine yet but picked up the snap ring pliers so I can this weekend. The problem is that I know one of my hubs has a blown out o-ring as half of it came out with all the gook I scraped out of there. I suspect that is what is causing it to hang up and not sure if I can get the parts to fix it.

Thanks for the update, it gives me a better idea of what is happening.

 

Us canadians do know how to fix something once in a while. Glad to have helped.

Kbear

 

I got in touch with the local Ford dealer to find out if there is a "rebuild kit" for the auto hubs. Of course I did this before I bought the manual hubs. The dealer told me that there is no such kit and that I would have to buy the hubs. The kicker is that one auto hub is $350! With that said, I think you will have a hard time finding any parts. I still have my old hubs and all the auto locking spindle parts. If you really want to get them off me, let me know. Email me at thecrewdawg@wideopenwest.com.

 

I put my vehicle up on jacks and tried engaging 4x4. The left front wheel would engage but not the right side. I pulled apart and thoroughly cleaned out the hub, got everything moving freely and put it all back together but it still would not engage. Taking it down the road still left me with the pulling to one side and vibration.

I swapped the auto hubs right to left to see if the right would engage with the working hub but it did not. In fact, neither side would engage.

I gave in and ordered a set of manual locking hubs. I was looking for the best price on Warn hubs and found what I thought was a great price and ordered them. I only noticed afterward that I had somehow stumbled on a different brand. Oh well, they were easy to install and are working and they only cost about $175. for the set delivered.

Unfortunately my original questions here were about my ujoints and whether some of my symptoms are related to the ujoints, how to diagnose them and what size job would it be to replace them. None of these questions were addressed unfortunately and I still have problems. I am pretty sure that the outer joint on the passenger side has gotten very stiff and is what was causing the vibration problem. Since I have been able to engage the 4 wheel drive with the manual hubs and have run it a few times it seems to have loosened up SOME. There is distinct vibration when in 4x4 mode that is not there when the shafts are not turning and when I turn hard either to the right or to the left it makes a clunking noise and feel.
I am now into deep cold and snow without a workshop though and this is my only vehicle so I am reluctant to start the project of replacing these not knowing what I may be getting into.


Thanks to everyone that helped with the lockout hub problems.
I had to use 4x4 in the snowstorm yesterday and it REALLY saved me. Conditions were terrible on a long highway commute and if I was only in 2wd I would have had a helluva time.

 

From earlier in this discussion:
Do any of the u-joints exhibit condition 1? If not, it will be hard to tell for sure that they are bad without removing them, and at that point you might as well replace them.
Replacing u-joints isn't too bad. I always thought Haynes had an adequate description of how to do it, so I expect if you followed the instructions in your Haynes manual, you'll be fine. My personal preference for tool is a C-frame ball joint/u-joint tool that can usually be borrowed from a place like Autozone. A vice and sockets will work well, too, though.
Driveshaft u-joints are pretty straightforward: remove the shaft then replace the u-joints. For that matter, I had a driveshaft shop tell me that, if I removed the driveshaft and bought new u-joints from him, he'd install the u-joints for free.
The two outer axleshaft u-joints are a little more involved because you have to remove everything on the steering knuckle to get outer axleshafts out. This isn't too bad, unless your spindles are seized onto your steering knuckle. On my '87, the spindles took everything I had and then some to get off. On my '92 they came off with just a few whacks of a soft faced hammer. The inner axleshaft on the passenger side is held in place by a C-clip inside the differential, so removing that shaft requires removing the differential from the axle beam. I haven't had to do that, yet, but those who have say it isn't too bad after you've done it once or twice. This inner u-joint isn't as prone to failure as the outer u-joints, and it will be easy enough to inspect once you get the outer shaft out.

 

How would you test condition 1? Just grab the shaft and see if it has enough slop to move it? Or do you need to exert more force on it and use something to pry and look for movement? I have no experience with them.

I had read somewhere else that sometimes you can replace the outer ujoint without pulling the shaft. I hesitate to try pulling the whole thing out and maybe not being able to get it back together as it is my only running vehicle at the moment. Well, there is the motorycle but it was -2 this morning and the roads are icy.

I may very well have problems with both sides but the one on the right wheel seems to be making all the noise.
I have a lot of front end vibration that is probably not related to the ujoints and have not narrowed that down either. When I swapped out the hubs for manual I did notice that the outer bearing was pretty loose. I torqued the new spindle nuts on which should have tightened them up properly but I still have vibration.