Alright, so my front end is starting to make noise again. Driver's side. I notice it only on dirt roads, there are three dirt roads that I drive on daily, and they've all got potholes and stuff, not smooth. It started as just a little crunching/scraping/squeaking noise randomly, sometimes when turning but sometimes not. For several days it would happen only in the mornings when it was cooler, but on my way home from work in the afternoon it would be fine.

I felt the hub after driving each time, and it never felt warm. I tried weaving back and forth while driving, in an attempt to see if it felt weird. Nothing. I jacked up the tire and spun it by hand, didn't feel anything out of the ordinary. Can't wiggle it top to bottom.

No noise on paved roads. Several times, at highway speed, I would drop the truck in to neutral and just coast for a minute, trying to catch a rumbling sound that's indicative of a failed wheel bearing. Never heard anything.

Well, this morning it was suddenly worse. A vibration in the steering wheel, and the noise was much more prevalent on the bumpy dirt roads. I finally decided to take the hub apart. It still didn't feel warm when I got home. I pulled everything apart, looked at the brake caliper/pads, nothing out of the ordinary there. Outer wheel bearing is fine, and although I didn't pull the inner wheel bearing out of the hub (don't want to mess around with the oil seal if it can be avoided) it spins just fine by hand, no resistance or noise.

It can't be a u-joint problem (I don't think) because I'm not in 4wd. When it first started happening, I was wondering if the shock was going bad because it only happened on the bumpy dirt roads. Now, I don't know. The vibration in the steering wheel is now making me wonder if the tie rod ends are bad.

I doubt it's a ball joint, because they're all just a year old.

I need this truck back on the road ASAP, but I'm not going to drive it with an undiagnosed problem and risk an expensive repair.

Any ideas what I should look at next?

 

Any chance it is your springs? Just a thought...

 

I suppose it could be the springs. However, I don't know how to go about diagnosing a spring problem.

At this point, I'm fairly confident that I've eliminated wheel bearings, u-joints, and ball joints as an issue. The only other moving parts in the front end are the springs, shocks, and tie rod ends.

 

Well I sat out there and tried my best to move the knuckle, I can't find any play in any direction. That leads me to believe that the tie rod ends are OK, as are the ball joints.

However, I grabbed the u-joint behind the knuckle and spun it, and there was definite scraping and resistance inside the spindle, where the axle shaft comes through. I didn't think the axle shaft spun in 2WD, unless the hubs were locked. Which they aren't, although I haven't tested them to see if the locking assembly failed. It's a Warn part, less than a year old, so it shouldn't have, but it's possible.

Thoughts?

 

Do the hubs unlock? Try to turn the axle shafts with the tires on the ground. They should easily turn.

 

In theory, yes, the hubs unlock. I haven't looked at the locking assembly I removed to see if it's working properly. I'll pull the locking assembly off of the passenger side and attempt to spin the axle shaft. That way I have something to compare the driver's side to.

 

Well I just went out and tried spinning the other axle shaft, and there was definitely a point where it provided resistance. Both of them are doing the same thing. They spin freely for most of a complete rotation, and then there's a point where something hangs up, and it resists spinning. But once you spin it past that point, it'll spin freely again until it comes around to the point of resistance.

When spinning the driver side axle shaft, the noise generated by the resistance sounds localized. When spinning the passenger side axle shaft, the noise sounds like it's coming from the driver side.

I can't imagine that it would be a front axle/axle shaft issue, because nothing is supposed to spin when the hubs are unlocked and I'm in 2WD.

 

Shameless bump cuz I need help

 

Alright, updated info... I learned that there is a "spindle bearing" inside the spindle that the axle shaft rides on. I suppose if I'd actually given it five seconds of thought, I would've realized that it was there, but for whatever reason I had no idea it even existed. So I pulled the spindle off to check it, and it looked fine. However, when I pulled the axle shaft out, I discovered that the u-joint is locked up. One half moves freely, and the other half is locked up tight.

To test the theory, I went back to the passenger side, sitting intact with the tire on the driveway, and spun the end of the axle shaft. All signs of resistance were gone, it spins 360 degrees completely freely.

So, hopefully I've found the culprit. A u-joint is simple to replace.

Also, it appears that this is a sealed u-joint. It's got caps on all four ends, instead of the clips I'm used to seeing. Is there anything different about replacing it that I should be aware of?

 

Well I'll get a new u-joint hopefully tomorrow, get it swapped in, and we should be back in business. The only thing that still hasn't been made clear to me is why I'd feel a vibration in the steering wheel at highway speeds. Some of the roads around here are rough, so I honestly can't say if the area where I felt it was normal or not... Guess we'll see.

 

I just meant with the hub unlocked, and tires on the ground, can you reach under the truck and rotate each axle half. If they turn, the hubs unlocked. A stuck u joint won't matter for 2wd vibration, but it can cause memory steer. If the hubs are working, dont expect the new u joint to fix your issue. Can you rotate the front driveshaft? Possible the tcase isnt shifting out of 4wd. If thats the case, u joint may make it feel fixed after all, but the tcase would need attention.

 

This u-joint is bound tight. When the truck turns, that u-joint has to flex, and when it can't do that, it would make the sounds that I've been hearing.

The transfer case isn't the problem. It hasn't been in 4WD in months. It wouldn't suddenly go from 2WD to "stuck in 4WD" after sitting in 2WD for six months.

I know the hubs unlock, because I tested both of them.

 

Ok, rereading your description in post #1 makes me agree with your diagnoses. Good find. For some reason, I had it in my head you were chasing a constant vibration--poor reading comprehension or memory on my part.

As for replacing the joint, maybe you know this already, the caps are retained with C-clips on the OD of the cap, on the inner side of the caps.

 

That part I did not know. The ends of the u-joint are labeled "+" and "-" on opposite ends, seemingly indicating to me that they have to be driven out and in a certain way due to the odd looking (to me) caps that retain them. I did not notice any c-clips, but I'll look again today. The c-clips are underneath the slip yoke?

 

The picture on left shows the slot in the caps that the C clip sits in. The picture on right shows the retainers found on a more typical rear driveshaft. My wording may have been unclear, thought an image would be better. I figured it worth mentioning bc often the clips are so crusted over they're hard to notice.

I'm not sure about the +/-, maybe other's in the know will chime in? Are the caps the same diameter or does the F250 use some kind of conversion joint (2 sets of different sized caps)?