Another knocking sound (resolved)

bedhed

bedhed

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Earlier in the year, I started hearing a knocking/clunking sound coming from (what seemed to be) under the driver's side. Turned out that the splines on my driveshaft was shot. Fast forward to the past few weeks, a very similar sound has returned and I have no clue as to wear it's coming from.

  • The sound seems to be coming from the front-left, and can be felt under my feet.
  • Happens when moving over uneven terrain, speed bumps, etc.
  • The sound goes away when using 4wd.

I replaced the previously worn front driveshaft with one from Tom Woods, along with the included Spicer joints. Both front and rear upper and lower (OEM) control arms were replaced a few months ago.

The part that's confusing me the most is the disappearance of the sound when I shift into 4wd.

Has anyone with this similar issue figured it out, or anyone have any suggestions? I went through a few threads, but none were resolved.
 
The sound has seemed to come and go, but I'm hoping that I have just found the culprit. Greased the front joint, and now I'm not hearing or feeling the clunk.

Would a new joint (in need of grease) cause a sound like that?
 
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bedhed said:
Earlier in the year, I started hearing a knocking/clunking sound coming from (what seemed to be) under the driver's side. Turned out that the splines on my driveshaft was shot. Fast forward to the past few weeks, a very similar sound has returned and I have no clue as to wear it's coming from.

  • The sound seems to be coming from the front-left, and can be felt under my feet.
  • Happens when moving over uneven terrain, speed bumps, etc.
  • The sound goes away when using 4wd.

I replaced the previously worn front driveshaft with one from Tom Woods, along with the included Spicer joints. Both front and rear upper and lower (OEM) control arms were replaced a few months ago.

The part that's confusing me the most is the disappearance of the sound when I shift into 4wd.

Has anyone with this similar issue figured it out, or anyone have any suggestions? I went through a few threads, but none were resolved.
Click to expand...

I had something similar.

For me.. it was a ujoint on the front driveshaft
 
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Sancho said:
I had something similar.

For me.. it was a ujoint on the front driveshaft
Click to expand...
Same here. With my first issue though. Turned out to be the same. Second time around was the driveshaft. How the splines wore down the way they did, I have no clue.

With this joint though, it's new. I don't know u-joints well enough to understand how it could produce such a noise. One that's in need of grease anyway.
 
bedhed said:
Same here. With my first issue though. Turned out to be the same. Second time around was the driveshaft. How the splines wore down the way they did, I have no clue.

With this joint though, it's new. I don't know u-joints well enough to understand how it could produce such a noise. One that's in need of grease anyway.
Click to expand...

I found that it was my front ujoint by the amount of play i had in the drive shaft.

You can check for this yourself, just get it off the ground... then wiggle the jiggles outta that sucker.

If there is movement between the ujoint caps and yoke... prob time for a new one.
 
Sancho said:
I found that it was my front ujoint by the amount of play i had in the drive shaft.

You can check for this yourself, just get it off the ground... then wiggle the jiggles outta that sucker.

If there is movement between the ujoint caps and yoke... prob time for a new one.
Click to expand...
Yeah, my original had play in it like that. A lot! This one doesn't though. The shaft and joints have less than 8,000 miles on them.

On another note, greasing the joint didn't fix the problem. Drove it on one of my normal highway routes just now and I could feel the tapping at my feet. So, it's doing it while I'm on the highway also, but it isn't constant.

Once I pulled into the driveway, I could hear and feel it just as it was before I greased the joint.
 
Ok
How about your sway bar endlinks?

I had some thumping due to the boot being rupped/worn out.

It eventually came apart and the thumping became a, "oh shit, what is that noise" sound.

The thumping was felt in the seat.. and was somewhat cyclical.
 
Sancho said:
Ok
How about your sway bar endlinks?

I had some thumping due to the boot being rupped/worn out.

It eventually came apart and the thumping became a, "oh shit, what is that noise" sound.

The thumping was felt in the seat.. and was somewhat cyclical.
Click to expand...
As best as I can tell, all of my steering components are all good. When I replaced the control arms a couple months ago, I went around and greased everything and didn't see or feel anything out of the ordinary.

The end links themselves, I replaced sometime last year.
 
This tapping that I'm feeling is somewhat cyclical too, at times, but my thinking changed with it recently when I drove over a "washboard" spot on a dirt road. At that point, it seemed more like a rattle. But tonight, I felt it as I was slowly pulling through a fast food drive.
 
Anyone else have some ideas? I've wracked my brain, but I can't seem to figure out what it could be.

I don't have the funds right now to pay someone $75/hr to do it for me, so any ideas would be great at this point.
 
I've had it when 4wd would calm a noise and also tighten up the steering feel in general. If it's not in the steering or front axle then you have to look at what else 4wd directly influences. Have you checked the trans mount? And engine mounts? And the skid bolts?
What happens when you pull the front driveshaft? And then put it in 4wd? If the removal of the shaft makes a difference it will likely be in the steering or front axle systems. If it makes no change then move elsewhere. Shaft pulled, engage 4wd, noise stops? Could be transfer case internals. If none of this helps, move on.
Replace front shaft, pull rear shaft. Engage 4wd. Does this help with the noise? Could be the rear shaft. Or rear axle. Who did SYE? it could be in there.
If none of this has helped yet take a real good look at ball joints, axle bearings, and brakes.
After all this all that is left is the exhaust system or a bad mount (track bar, control arm, Antisway bar, body.

That is the way I would go to track it down. If it is tied to the vehicle speed it should be found somewhere in the drivetrain systems. Or you have tire/wheel loose, but I'm sure that was checked loon ago.
 
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Goatman said:
I've had it when 4wd would calm a noise and also tighten up the steering feel in general. If it's not in the steering or front axle then you have to look at what else 4wd directly influences. Have you checked the trans mount? And engine mounts? And the skid bolts?
What happens when you pull the front driveshaft? And then put it in 4wd? If the removal of the shaft makes a difference it will likely be in the steering or front axle systems. If it makes no change then move elsewhere. Shaft pulled, engage 4wd, noise stops? Could be transfer case internals. If none of this helps, move on.
Replace front shaft, pull rear shaft. Engage 4wd. Does this help with the noise? Could be the rear shaft. Or rear axle. Who did SYE? it could be in there.
If none of this has helped yet take a real good look at ball joints, axle bearings, and brakes.
After all this all that is left is the exhaust system or a bad mount (track bar, control arm, Antisway bar, body.

That is the way I would go to track it down. If it is tied to the vehicle speed it should be found somewhere in the drivetrain systems. Or you have tire/wheel loose, but I'm sure that was checked loon ago.
Click to expand...
Lots of info there. Thanks.
As far as the trans and motor mounts, both were replaced around the same time, roughly 4 years ago I believe. I'll get under it today and get a closer look at those to make sure.
The skid bolts I replaced around 2 years ago too. Had a stripped rivet nut, so I replaced them all. Checked those and didn't get a rattle.

I haven't tested it with the shaft pulled. Hadn't thought of that. I'll try it.

Your mention of transfer case internals has me curious. Of all things, that's what it feels like under my feet. The sound is very low and hard to hear, but easily felt by my feet, as if it's something very close to the tub. If I pull the shaft and the noise remains, it could still be the TC, correct?
 
John Scoggins said:
Have you checked the front axle u-joints for play?
Click to expand...
I did. The details of that are listed above.

Well, thus far I have only checked the trans mount, which appears to look great.

I was finally able to get a buddy to walk alongside while I drove across some areas. I'd drove across his yard earlier and heard the sound. But of course when we went out to try locating it, I couldn't reproduce the noise.
 
If you feel it in your feet it is less likely to be a front axle/steering problem. They are generally transmitted through the steering wheel. So I would pull that rear driveshaft and go from there.
 
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Goatman said:
If you feel it in your feet it is less likely to be a front axle/steering problem. They are generally transmitted through the steering wheel. So I would pull that rear driveshaft and go from there.
Click to expand...
The rear driveshaft is the original, as far as I'm aware. Nothing has been replaced on it since I've had it, so that would make sense if it was coming from there.

As I typed that, I had the question of why the sound stops when 4wd is engaged? If it is in the rear driveshaft. Does that still run inline with your thinking?
 
Somehow I got it in my head the sound was cyclical with mph. If it is only when hitting a bump then I apologize for giving crap advice. That is an entirely different question than the one I was trying to answer.
 
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