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Discussion Starter · #1 ·
I have a '99 WJ with only 56K miles on it. bought it last week. I have noticed that there is a definite clunk from the rear after stopping while still in drive. I have the 4.7 V8 and Quadra TracII. I am new to this system. The clunk occurs after being stopped for about 5 seconds but the time lapse varies from two seconds to about 20 seconds. The clunk doesn't happen at any other time. When it does happen I can feel it as well as hear it.
Any info would be appreciated.
Thanks
 

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Discussion Starter · #2 ·
Re: Clunk in Read Differential

I'm rethinking the noise and it may be the transfer case I suppose and My hearing is not that great. I just can't figure out what could be making the clunk noise after the car has come to a complete stop and has been idling at a stop light for several seconds since nothing should be moving. Makes no sense to me. The clunk noise does not happen if I shift into neutral before I come to a complete stop and doesn't happen when I put the trans back into gear.
 

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The beast from Brazil
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Re: Clunk in Read Differential

Thinking about it, i had something alike happening after my transmission rebuild. It was finally the transmission shifting from 1st gear into 2nd gear with the jeep standing still.
There are 5 pressure switches in the TRS/solenoid assy which are used as a feedback signal to the TCM. When the TCM selects a gear, the pressure switch shows the TCM that the pressure is there.
If the signal is not received, the TCM thinks that 1st gear (in this case) is not selected and it will take 2nd gear instead. This shift is felt as a clunk, due to the releasing of one clutch and then applying of an other clutch. On my jeep the fault was with one of the pressure switches.
Did you check if a DTC is set? To do so, do the key dance: switch ignition switch off/on three times and leave it in on at the third time. The odometer will show " DONE" when all ok, or any fault code.
 

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Re: Clunk in Read Differential

I too have been thinking... If you were to do a "stop and go" and take off again before the clunk decided to say hello how does the jeep feel?
Does it take off in first, or does it seem to be bogged down and possibly in second?
 

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Discussion Starter · #6 ·
Re: Clunk in Rear Differential or T-case

I tried doing the key dance but nothing showed up on the speedo. I have an OBD-II scanner but it is not showing any codes. I'll try the stop and go before the clunk happens to see what happens and let you know.
Thanks for the replies.
 

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The beast from Brazil
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Re: Clunk in Read Differential

When i had this problem before and it went into 2nd gear, i didn't realise it at first. The torque converter let it all go fluently and the engine has power enough to take off in 2nd. I only had a fault code set, which made me start trouble shooting and find out what was going on.
You should try to compare the acceleration after a stop without the clunk with one with the clunk, to see if you will feel any differences, which could confirm the "being in 2nd" gear theory.
 

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Discussion Starter · #8 ·
Re: Clunk in Read Differential

I did the stop and go several times, with and without the clunk and it always took off in first gear. I'm going to get under it this weekend just confirm that nothing is loose. I get a lot of noise out of moaning out of the rear brakes, the sound is that which is made when you don't have your foot on the brake pedal hard enough and the car wants to pull ahead. Probably totally unrelated but will check it out.
Is the transmission sensor that you mentioned something that can be changed easily and if so I might change it out just for peace of mind.
Thanks for any info.
 

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Re: Clunk in Read Differential

Mine moans like crazy as well. Frango100 will have to answer the sensor question, I am unsure what sensor he was hinting at. There is a transmission speed sensors that are on top of the trans driver side accessible from the ground. One in the front (input), and one towards the rear (output) and both SHOULD be the same part number.
Usually with the sensor you will get a code if it is failing or has failed like what happen to Frango100
Does this clunk happen every time? If you roll forward at an idle and stop again does it clunk again?
 

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Discussion Starter · #10 ·
Re: Clunk in Read Differential

No codes wih my scanner and no check engine light. Did the key dance again and it worked this time and the word DONE came on the speedo. I does not clunk on the first few stops and seems to be a bit more pronounced if I stop harder. If I slow the car to a gentle stop it does not clunk. I does not clunk again if I roll forward at idle. It always starts in low. I'm thinking more and more that something is loose.
I really appeciate all the replys and suggestions.
 

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The beast from Brazil
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Re: Clunk in Read Differential

The TRS/solenoid assy is not a sensor, its in fact the electric/hydraulic heart for the transmission shifting. It has 5 clutch control solenoids,1 pressure control solenoid, 5 pressure switches and several switches which are actuated depending on the shift lever position. Its inside of the tranny, mounted on top of the valve body. Not a very cheap item to change (approx. USD300 + filters + fluid + rtv), so you need to be sure that the problem is in there. When you have a speed sensor problem, you probably get a code set and for sure the shifting will be harsh.
Can it be that you release a bit the pressure on the brake pedal and that then the clunk shows up? I would indeed check the rear brake components and especially the 4 nuts which hold the brake backing plate on the back side, those nuts tend to come loose sometimes.
 

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Discussion Starter · #14 · (Edited)
Got under the car this morning and could find nothing loose. Looked forward toward the transfer case and could see seepage from the rear seal so I'm guessing that the transfer case is low on oil. Im thinking I can change out the seal myself but not sure if there is a special lubricant for the TC and can I get something at autozone or O'reilly? I'm hoping that the clunking just turns out to be low lubrcant in the TC.
Thanks for any info!
 

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Discussion Starter · #15 ·
Not sure my last post went through but have determined that the probable cause of the clunk is actually low oil in the transfer case as I discovered that the rear seal is leaking. I have been all over the net trying to determine what lubricant to use in the transfer case. The Mopar only fluid turns up most often. However, in looking at my owner's manual it clearly says Dexron III trans fluid or equal so now I'm confused?!?!:confused:
 

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The beast from Brazil
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Since your jeep is quadra trac II, it has the NV 247 T case. This T case requires special mopar fluid, which in fact is just Mobil 424 fluid. When the WJ came out in 99, they used ATF+4 in this T case, never heard from Dexron III in here. Soon they changed to the Mobil 424 after having problems with clutch chatter.
It is quite normal to have a bit of fluid coming from the aft seal. The propellor shaft has a slip joint with the T case, this is necessary due to the travel of the suspension. Because it constantly moves a bit in and out, a bit of fluid can come out. If its leaking a lot ofcourse is not normal. Don' t know why the T case would make a clunking noise when standing still when the fluid level is low, but it wont hurt to check.
 

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Discussion Starter · #17 ·
Thanks Frango...I'm grasping at straws right now. There is more than a little seepage as the tailshaft of the TC is a dark brownish yellow and oil is spread out on the under carriage from the driver's side to the passenger side in about a 12" swath so there is some slinging going on. The oil in the TC, the tranny and differentials has never been changed so I'm thinking I'll get it into the shop and have that done.
 

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Just picking up on the clunk you get when at a stand still, I to have had this problem and have just ignored it since I have owned my WJ.
I will be changing out all control arm bushes and the ball joint in the rear as they are flogged out.
Will have to wait to see if that makes a difference as parts won't arrive for another 2 weeks.
 

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The beast from Brazil
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Worn bushings and or upper ball joint can cause clunking, especially when going over bumps. I had bad upper control arm front bushings and could feel.it a lot in the steering during highway driving, i had to correct the steering wheel constantly.
He Ipahihi, did you order new bushings, or complete.new arms? I hope.that you didn' t go with Omix ada bushings, because.the ones i changed just last less then 1 k Km. I have Dorman bushings now and i could.see the quality difference right away. The Dormans are holding up quite.nice.
 

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Went with the new arms as pricing was marginal and the swap out will be a lot quicker. However, the postage as always was a killer.
We are not subject to import taxes in Australia unless spending over $1000.00.
 
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