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Discussion Starter #1
Apologies for all the maintenance questions being a new member. Just got it a few weeks ago and trying to work through all the bugs. Anyone have insight to a "thunk/ clunk" sound coming from the front end (you can feel it in your feet as well)? - really noticeable when backing out of the garage and turning to go forward up the driveway - CV joints? Rack? Again - appreciate any/ all input - once i get it sorted out i plan to move to the lifting forum :icon7:
 

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What Engine/Trans/4WD system does it have? QTI/QTII/QDII?

The QDII has LSD's and I have seen posts about over due fluid changes causing some binding in the LSD's.

Other possibilities are Differential, Front Differential Mounts, Front driveshaft, and Transfer Case.

Need to inspect all those items.

I have had a slight clunk every once in a while when the preload changes on the drivetrain, usually low speeds, going from coasting to power onto the vehicle. I suspect I may have a little stretch in the chain in the XFR case. All my items check good, but there is some lash in the output of both front/rear of the xfr case. And lash (free play) is what creates clunks when load comes off and goes on the drivetrain.
 

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check the upper front differential mount...that's where mine was hiding
 

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Discussion Starter #4
What Engine/Trans/4WD system does it have? QTI/QTII/QDII?

The QDII has LSD's and I have seen posts about over due fluid changes causing some binding in the LSD's.

Other possibilities are Differential, Front Differential Mounts, Front driveshaft, and Transfer Case.

Need to inspect all those items.

I have had a slight clunk every once in a while when the preload changes on the drivetrain, usually low speeds, going from coasting to power onto the vehicle. I suspect I may have a little stretch in the chain in the XFR case. All my items check good, but there is some lash in the output of both front/rear of the xfr case. And lash (free play) is what creates clunks when load comes off and goes on the drivetrain.
QD2 - not a pre-load issue, sounds more like a limited lip without additive in it - fluid change sounds like a good plan of attack, along with looking over everything and verifying tight............
 

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I experience the same when taking off occasionally- like second after the vehicle gets moving.
Mines a QuadraDrive II and a V6 CRD- so more lower down torque I presume than what the V8s experience.
Let us know your outcome as I'm sure it would benefit many.
 

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What Engine/Trans/4WD system does it have? QTI/QTII/QDII?

The QDII has LSD's and I have seen posts about over due fluid changes causing some binding in the LSD's.

Other possibilities are Differential, Front Differential Mounts, Front driveshaft, and Transfer Case.

Need to inspect all those items.

I have had a slight clunk every once in a while when the preload changes on the drivetrain, usually low speeds, going from coasting to power onto the vehicle. I suspect I may have a little stretch in the chain in the XFR case. All my items check good, but there is some lash in the output of both front/rear of the xfr case. And lash (free play) is what creates clunks when load comes off and goes on the drivetrain.
I just bought my limited hemi with QDII, and does exactly what you're saying. If I had load on it, and let off to coast, then tap it again, it clunks, at lower speeds. Also when I back out of the driveway, and shift into drive.
 

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Sway bar bushings and end links cause noise. Sounded like a rattle to me more than a clunk though.
Yes, end links having a lot of play can cause rattles or banging.

I've had clunks from bad bushings, and its usually the hole in the bushing elongates and has open space, so when you turn and the sway bar twists and goes under load, it will push the bar toward the other end of the elongated hole in the bushing, when it hits it and stops, you'll get a clunk.

So, if you can see space between the bar and the bushing, and the vehicle swaying from one side to the other creates a clunk, its the bushings. NOT in all cases, but I've experienced it.
 

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I just bought my limited hemi with QDII, and does exactly what you're saying. If I had load on it, and let off to coast, then tap it again, it clunks, at lower speeds. Also when I back out of the driveway, and shift into drive.
Check the drivetrain, look for obvious things wrong in the driveshafts and components. Try to twist the driveshafts, and twist the ends (outside the joints) while trying to twist the actual shaft in the center.

The should NOT be any free play in the driveshafts and the joints on their ends. There is normally a little free play inside the differentials, so you can twist a driveshaft on either side and get a couple of degrees of free play. The front/rear output of the xfr case has a differential in it as well and the same applies. In my case, I get more than a few degrees of free play between front/rear outputs.

Could be wear in the differential in the xfr case, or more likely, there is a long chain that transfer torque to the front output, and they are known to stretch as they wear. So I'm assuming my clunk is a stretched chain in the xfr case. Eitherway its NOT so bad that I can't live with it, wait till it gets much worse before I rebuild the xfr case. I did change the fluid though.
 
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