another wheel bearing question on 2002 (replaced driver side and still have hum/vib)

[stunya]

Hey all, new to the forum! Really love all the information that is available. My father in law has an 02 Explorer 4 door with the 4.0 (92k miles). He has been having some issues with a terrible hum and a slight vibration (all sounds come from front drivers side). Classic symptoms of wheel bearing failure as described in various threads. As you turn the wheel slightly right, the noise goes away, but center to left, and the noise is present.

Immediately suspecting a drivers side wheel bearing failure, we replaced it last weekend (it looked terrible, bearing was slightly seperated, etc). The noise is still present. Without performing any more random shots in the dark, should i replace just the passenger side front, or all of the other 3?

This truck only has about a year left in the family, but i surely want it safe to drive.

I am 3 hours away and want to be sure i get it right this time. What are other things that could be failing to create this situation (cv-rotates well with no noise, and transfer case engages all modes of 4wd without a problem)?

Thanks in advance for any help. All input is greatly appreciated.

 

[imp]

These vehicles have quite a large number of possible noise sources due to failed components. Add to that the variety of differing descriptions of the nature of the noise (whine, bumping, roar, grinding, etc), throwing out suggestions is just that: Ford Shop Manual has a section devoted to noise in which the types of failed-component noise produced are categorized by nature of the sound vs. what component failed. It would help greatly if more could follow their guidelines. I will post Ford's noise page later.

Now, your case is a perfect example asking for noise-check while running. Since you seem fairly certain it originates in the front driveline, I would place all 4 wheels off the ground, supported by jackstands at the closest possible support point to the wheels, and allow the driveline to spin in Drive slowly, while using a probe (stethoscope) to isolate the origination point of the noise as closely as possible. If not an AWD, you MUST use 4X4 HIGH range to ensure both F. & R. axles turn at the same speed. A better way is to remove the rear driveshaft first, but it's more work.

I have done this process, and find it much better than haphazardly guessing at noise source, replacing parts, and having no success eliminating the noise. I DO NOT recommend this be done by anyone not having had a reasonable amount of work experience on motorized vehicles! imp

 

[stunya]

imp...thanks for the feedback. that is definitely the right way to do business and i really wish i would have done that while i had the truck here. I believe i am competent enough to perform that evaluation, but may be worth paying the ford techs to do it and then just not having them perform the work.

Ill keep looking into it. Thanks for the feedback and the great idea. Love to see that troubleshooting noise sheet!