Author Topic: strange noise... rear diff maybe?  (Read 2425 times)

tx_country

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strange noise... rear diff maybe?
« on: April 25, 2009, 10:55:16 PM »
So while I am driving I hear a strange noise from under the jeep. It stops when I stop. Thinkin maybe the diff because the dealer told me the vent tube is missing last time I took it in. And I have put it through some mud and water... Any ideas or suggestions? If anyone has time tomorrow (sunday), I'd like a more experienced and knowledgeable opinion...

Offline Axle

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Re: strange noise... rear diff maybe?
« Reply #1 on: April 26, 2009, 02:15:46 AM »
Could be a u-joint.  If the diff is full of mud water, buy some Blue or Black RTV and some 80w90 diff fluid, pop the cover and drain the old fluid.  If it's full of mud water, then you'll know what the problem was and pray it didn't destroy any of the bearings.  Before you do that, however, crawl underneath the jeep and check both of the drive shafts for excessive play.  That could indicate a ujoint.
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Offline kirksjeep

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Re: strange noise... rear diff maybe?
« Reply #2 on: April 26, 2009, 02:18:23 AM »
Could be a u-joint.  If the diff is full of mud water, buy some Blue or Black RTV and some 80w90 diff fluid, pop the cover and drain the old fluid.  If it's full of mud water, then you'll know what the problem was and pray it didn't destroy any of the bearings.  Before you do that, however, crawl underneath the jeep and check both of the drive shafts for excessive play.  That could indicate a ujoint.

Great Advice.  Start with the cheap and easy things first. 
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tx_country

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Re: strange noise... rear diff maybe?
« Reply #3 on: April 26, 2009, 02:21:11 AM »
If I can't figure it out tomorrow we can always check it out at the meeting. Thanks for the advice... If I have any problems or questions I'll be callin someone

tx_country

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Re: strange noise... rear diff maybe?
« Reply #4 on: April 29, 2009, 03:52:10 AM »
so i have eliminated the diffs, and narrowed the source of the sound down to the front left. checked the brakes, they look good. drive shafts, everything looks good. sounds like a metal on metal rubbing noise, gets louder when i turn left and is intermittent when going straight. not sure what it could be. any ideas?

Offline calvynandhobbs

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Re: strange noise... rear diff maybe?
« Reply #5 on: April 29, 2009, 04:08:43 AM »
Sounds like a wheel bearing unit. Try lifting that side off the ground, grab the bottom and top of the tire and see if there's any play in the wheel bearing or in the ujoint on that side.
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Offline kirksjeep

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Re: strange noise... rear diff maybe?
« Reply #6 on: April 29, 2009, 04:27:11 AM »
Sounds like a wheel bearing unit. Try lifting that side off the ground, grab the bottom and top of the tire and see if there's any play in the wheel bearing or in the ujoint on that side.
X2

Any vibs in the steering wheel or brake pedal?
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

tx_country

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Re: strange noise... rear diff maybe?
« Reply #7 on: April 29, 2009, 04:36:22 AM »
No vibs what so ever. Ride is good. Had it up on the jack earlier with no play in wheel. It has me and another guy from the boat stumped. Gonna try greasing and cleaning everything

Offline Axle

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Re: strange noise... rear diff maybe?
« Reply #8 on: April 29, 2009, 01:29:52 PM »
That sounds like your u-joint between your inner and outer shaft on that side.  You may not see any play in the joint, but if it's dry, it will make noise.  The way you described the sound is right in line with that.
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PaulW

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Re: strange noise... rear diff maybe?
« Reply #9 on: April 29, 2009, 01:47:41 PM »
then again keyboard diagnosis isn't an exact science :D

Offline Axle

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Re: strange noise... rear diff maybe?
« Reply #10 on: April 29, 2009, 01:48:45 PM »
My keyboard is calibrated.  ;)
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tx_country

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Re: strange noise... rear diff maybe?
« Reply #11 on: April 29, 2009, 04:37:02 PM »
Axle- recommend greasing? Any grease I should use? Not too familiar with greasing anything but a torpedo room

Offline Axle

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Re: strange noise... rear diff maybe?
« Reply #12 on: April 29, 2009, 06:29:53 PM »
Those u-joints are not greasable.  You will have to replace them if they are bad.  Even if it's only the one side, I would replace both.  Since you still don't know what the exact problem is, however, I wouldn't go buying new u-joints just yet.  Keep trying to find it.
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Offline rocket

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Re: strange noise... rear diff maybe?
« Reply #13 on: April 29, 2009, 08:12:24 PM »
check also your anti-sway bar.  if it is loose, it will clunk, almost at random.  Mine was loose and it sounded like a loose rim, a loose coil over or something in the steering.  turned out to be easy and free to fix
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PaulW

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Re: strange noise... rear diff maybe?
« Reply #14 on: April 30, 2009, 02:35:51 PM »
check also your anti-sway bar.  if it is loose, it will clunk, almost at random.  Mine was loose and it sounded like a loose rim, a loose coil over or something in the steering.  turned out to be easy and free to fix

took out the sway bar didn't ya??