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Unread 11-11-2008, 12:18 PM   #1
rikkards
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Trying to figure out a knocking noise on takeoff in 2WD

Let's see if I can give enough info, first the Jeep:
98 Jeep TJ
2" BB
Stock shocks, springs, pretty much stock everything
31x10.5 tires
At least one of the front U-bolts was replaced this year before I got it and the front ball joints as well after I got it but it was doing it before.
I have had this annoying rattle noise on take off and have finally got around to trying to figure it out. When I took it in last, they mentioned there is a bit of clutch chatter and I always attributed it to that (never heard chatter before so I assumed this is what they are talking about).

However I found I can replicate it when starting in second gear. Also when I go into 4hi and lo it doesn't happen. Would clutch chatter still occur in these situations? It only happens from a stand-still

It sounds like something is loose and banging around. It is a little difficult to figure out what is causing it. Since it doesn't happen in 4wd I would take a guess that it might be the front driveshaft?
I am also not sure but I think it might be getting louder (either that or it wasn't as loud before as I usually have the stereo at a higher volume than I had today).

Any suggestions on how to figure out what might be the culprit?

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Unread 11-11-2008, 12:36 PM   #2
06rubicon
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could be the transfer case linkage knocking on the floor next to the gas pedal...see if that is the area...that linkage will flex close to the floor during take off situation and would gain clearence shifted into 4 hi or low.
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Unread 11-11-2008, 12:54 PM   #3
rikkards
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You know what, I think it is that. Mine looks exactly like the before picture:
http://www.4x4xplor.com/images/tcase...14_48_full.jpg

I am calling the dealer to get the part as mentioned in this link:
http://www.4x4xplor.com/T-CaseTSB.html
Thanks, I'll let you know if that fixes it.

UPDATE:
I ordered the part and should be at the dealership in a couple of days. $30Cdn which is not a steal but not exactly cheap but I am not sure what it consists of. Definitely a better deal than getting conductive adhesive for $11 at Canadian Tire.

At the same time I asked for a quote on the wires for the defroster grid on my Hardtop. I gave him the part number and he quoted $300 WTF!!!??!!!
From what it looked like in the picture in the Mopar Parts catalogue, the wire is spiraled and maybe 2 feet long with a clip that attaches to the window, a rubber grommet to seal the hole in the hard top and a plug that plugs into the wiring harness. The part number was 56009120AC. Can anyone else verify that this:
1. Is the right part number
2. Is the right price? If possible can you call your local dealer and get a quote on that price?
My existing wires have lost the spiral and are pretty ragged with some fraying. I would like to get them replaced but not for 300. Be cheaper to buy some shrink tubing and fix it myself.

Quote:
Originally Posted by 06rubicon View Post
could be the transfer case linkage knocking on the floor next to the gas pedal...see if that is the area...that linkage will flex close to the floor during take off situation and would gain clearence shifted into 4 hi or low.

Last edited by rikkards; 11-11-2008 at 03:46 PM..
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Unread 11-11-2008, 01:47 PM   #4
A2SuperCrew
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I used that TSB kit, and it did the trick. No more knockin' on the floor.
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Unread 11-14-2008, 05:23 PM   #5
rikkards
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Ok, taking the bracket off was easy-peasy but I am trying to get it back on with the new bushing but the new bushing is only going on maybe about an inch as it is pretty tight. Should it go further on to the shaft? Problem is, it is making it difficult to maneuver the bracket back to the holes? Any suggestions?
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Unread 11-17-2008, 10:22 AM   #6
A2SuperCrew
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Here's the write-up I followed when I did mine:

http://www.4x4xplor.com/T-CaseTSB.html

I do remember it was a struggle to get the bracket lined up on the body, but don't recall exactly what I did to do it.
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Unread 11-17-2008, 02:47 PM   #7
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I tried this weekend using the same instructions but I think the bushing wouldn't go on very far. Worse still, I couldn't get it to come back off.

Of course I left this until the weather was 49 deg F and raining so I was completely soaked and could feel my core temp dropping, it took about an hour and a hot shower to get back to normal. At that point, I figured my weekend off was worth more than screwing with this and decided to take it in for the mechanic to finish it. Fortunately I don't need it this week.

Quote:
Originally Posted by A2SuperCrew View Post
Here's the write-up I followed when I did mine:

http://www.4x4xplor.com/T-CaseTSB.html

I do remember it was a struggle to get the bracket lined up on the body, but don't recall exactly what I did to do it.
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Unread 01-24-2012, 09:25 PM   #8
vanek11
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not to revive a really old thread but these seem like the exact same symptoms I am having..
Here is the fullest description I can give, there is a clunk or rattle when I take off from a dead stop, it goes away right away, only rattles for a few seconds and only on take off, this however only happens in 2wd and does not happen in 4wd.
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Unread 01-25-2012, 03:43 AM   #9
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Wow Zombie thread
Sounds like you might have it. You might be able to move it by hand and make it hit the tub. If you can move it then you definitely have it. If you do replace the bushing, I think if you loosen the linkage it will make it easier. I heard someone ran a wire through two of the holes and through the bracket and had someone pull up on it line up the bolts when putting it back on
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Unread 01-25-2012, 03:07 PM   #10
Snydermann
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I also have the knocking/thumping sound while accelarating in 2wd. AND now my 4WD has problems disengaging. I need to crawl under at take a look at the linkage.
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Unread 01-26-2012, 06:15 PM   #11
vanek11
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It was def my linkage bushings, no sound now what so ever, entire ride is sooo much quieter. Def worth the $25. Heres the link again with part #s and instructions....
http://www.4x4xplor.com/T-CaseTSB.htm
Thanks again to OP cause I was banging my head and just throwing money at it.
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