[southernfryedyankee]

I have a 99 JGC WJ I6 and I had noticed this sound a couple of days ago upon acceleration past 35 MPH there is an "off" sound with slight vibration, it does not sound metallic but more like a evenly spaced hum that gets louder as I accelerate. I replaced the Wheel hub assembly last night but the sound is still there. My friend said that it could be the passenger side bearings going bad and It may be resonating to my side and I had planned to replace the passenger side today anyway. It only does this at 35 MPH+ and seems to immediately disappear when the vehicle slows down. I cannot tell if anything is loose and if it was just wind underneath the jeep it would seem that the sound would not be so evenly paced. Any opinions?

 

[Frango100]

Just to be sure check the front diff fluid and T-case fluid. The problem could be the passenger side wheel bearing, but also one of the CV joints in the front drive shafts or a CV/U-joint in the front propeller shaft (the one between the T-case and front diff).

 

[southernfryedyankee]

Do I have a transfer case? I have 2wd and where is the front differential to add fluid?

 

[Frango100]

Do I have a transfer case? I have 2wd and where is the front differential to add fluid?

You didn't say that in the first post. So no T-case and no front diff. Not much more left then the other wheel bearing or some road dirt stuck between the brake disc and fixed plate.

 

[southernfryedyankee]

I have taken a short video, maybe this might help.

99 Jeep Grand Cherokee humming noise when accelerating. - YouTube

 

[bill_de]

It sounds exactly what I heard in my 2014 last week. At first I looked around to see where the little motorcycle was so I didn't hit him, but he wasn't there. I put the Jeep in neutral at 40, with my foot off the gas. It didn't change the sound until we started slowing down.

The dealer diagnosed it as a wheel bearing. They had to order one, so I can't confirm that is it. However I'm pretty sure they are correct.


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[southernfryedyankee]

Thank you Sir, I am keeping my fingers crossed that that is all it is. Did he make mention if it was coming from the front or the rear? Would you feel and hear the vibration from the rear?

It sounds exactly what I heard in my 2014 last week. At first I looked around to see where the little motorcycle was so I didn't hit him, but he wasn't there. I put the Jeep in neutral at 40, with my foot off the gas. It didn't change the sound until we started slowing down.

The dealer diagnosed it as a wheel bearing. They had to order one, so I can't confirm that is it. However I'm pretty sure they are correct.


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[Frango100]

Drive around with someone in the back and see if that person also hears the noise coming from the front. It could eventually be a rear wheel bearing or rear differential bearing. Have a look at the rear differential fluid level and after a bit of driving take a small fluid sample from the diff fluid and check if its clean with no metal glinsters.

 

[southernfryedyankee]

I will definitely do that. I would have to remove the gas tank shield wouldnt I?

Drive around with someone in the back and see if that person also hears the noise coming from the front. It could eventually be a rear wheel bearing or rear differential bearing. Have a look at the rear differential fluid level and after a bit of driving take a small fluid sample from the diff fluid and check if its clean with no metal glinsters.

 

[bill_de]

Thank you Sir, I am keeping my fingers crossed that that is all it is. Did he make mention if it was coming from the front or the rear? Would you feel and hear the vibration from the rear?

The tech said he isolate it to the left front. There was very little vibration and gave the impression it was from the front.


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[southernfryedyankee]

OK, I will hopefully be knocking out the other bearing assembly today anyway.
Cross your fingers

The tech said he isolate it to the left front. There was very little vibration and gave the impression it was from the front.


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[southernfryedyankee]

Got it fixed, passenger side wheel bearing was shot. We replaced it and sound is eliminated Thank you all for all the advice and input.

 

[bill_de]

Great. :thumbsup:

Now keep your fingers crossed that the dealer has that kind of success with mine.


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