grinding noise from front driver side

At this point I'm baffled. I've been hearing a grinding/rattling noise from the driver side wheel well for a couple months now. I was positive it was being caused by a bad hub, but the problem persists.

here is what I've done so far:



replaced brake pads and rotors -- twice; once before the hub went bad and once after. The bad hub warped the driver side rotor and afterwards passenger side would not stop squealing for some reason.
replaced faulty wheel hub -- The bearing was totally shot, nearly 20* of play in it, should be totally rigid
replaced faulty CV axle -- I suspect vibration from the bad hub destroyed the outboard CV joint, making popping/grinding noise while turning or going over bumps
filled front differential -- it was a bit low on gear oil

The grinding/rattling noise shows up when driving at freeway speed (around 55mph) and gets more pronounced as speed increases. The truck does not do this under acceleration but after speeding up, the rattling is the worst at light throttle (around 2k-2.5k RPM, in 4th gear/overdrive above 55mph).


I noticed that if I shift into neutral at freeway speed, the noise continues until the truck decelerates.


So at this point my thoughts are that it could be a bad differential, but I doubt it because the noise is almost imperceptible in the passenger seat. It could be a bad differential bearing on the drivers side (sounds like a worn out bearing to me). It could be any number of things in the transfer case or transmission.


Anyone else had a similar problem, or any suggestions?

NOOb, have you figured out anything yet? Interesting problem especially not hearing it from the passenger side. Do you feel feel any vibrations at all?

I haven't found anything yet. I plan on taking the cover off the diff this weekend and inspecting things.

NOOb-un-2, let us know if you notice anything, usually if the diff. is bad you hear the noise some at low speeds. I wish I was a little more familiar with your vehicle so I could help more. Good luck.

which is why I'm inclined to believe its not something inside the differential. I'm leaning towards it being a worn out race on the driver side output shaft from the diff (where the cv axle mates up to). On most Durangos the output from the front diff is female, but on the 5.9L 4x4 it is a male splined shaft.

Considering the fact that the driver side hub bearing went bad, followed by the driver side CV axle and yet I'm still hearing a noise, the only thing left is the diff itself. but since I'm hearing the noise only on the driver side I'm guessing the internals are fine. However, the differential is offset on the driver side so it could in fact be internal to the diff. We'll see.

NOOb, good call on that race, these kind of problems are tricky to diagnose sometimes. Good luck and let us know how it turns out.