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MMXVI - L2H2 in Indiana
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turns out the clunk is because somehow both hub/rotor alignment dowels on both sides have sheared (or been cut) off. The clunk is the rotor hitting the lug when changing between P,D,R.
So you're saying the dowels(red) were sheared off and shifting caused the hub(blue) to rotate while the rotor(pink) was stationary and there is enough slop in the rotor bolt holes to allow that movement?

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2020 PM 2500 159"
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Can you explain what the relevance of the similarity to the Euro car hub is?
Many Euro vehicles use a similar hub, rotor, and lug bolt design. Many of which have no dowel pins and make no noise. It seems as @Prev1 and @phil asked, lug bolts would have to be loose, very loose to allow rotor movement when shifting from P to R etc.
 

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2014 PM3500 159 EXT high roof, 3.6L Gasser
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Discussion Starter · #26 ·
Alright, to address what i can: el jefe, i bought the cheapo version off rockauto, rather than reman OEM. My fault, and old guy is just a patient at my clinic so not putting too much stock in what he says.

To the hub alignment dowel questions: I was thinking that there was enough slop in the lug holes in the rotor, that the rotor was clunking against the lug nuts when changing direction. After some thought (that wasn't immediately after wrestling with a somewhat taxing and definitely expensive driveway repair), I've come to the conclusion that I am... unsure. the clunk is gone. It used to occur when switching from P/D/R regardless of whether brake pedal was depressed or not. Could that have been a bit of play in rotor lug holes? yes. could it be play in the aftermarket cheapo CV axles? yes. do I know which? no. Do I think that there is some braking force applied to those alignement dowels? absolutely! how else would they shear off?

Am I going to unbutton everything, remove the jury rigged alignment dowels, button her back up and then test? likely no. If I do i will update. thanks for coming to my TED talk.
 

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2014 PM3500 159 EXT high roof, 3.6L Gasser
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Discussion Starter · #27 ·
Many Euro vehicles use a similar hub, rotor, and lug bolt design. Many of which have no dowel pins and make no noise. It seems as @Prev1 and @phil asked, lug bolts would have to be loose, very loose to allow rotor movement when shifting from P to R etc.
Lug bolt were on so tight that i had to buy a longer breaker bar, as my cheap 350ft/lb air impact would not budge the lug bolts and the factory tire change kit bent.
 

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2014 PM3500 159 EXT high roof, 3.6L Gasser
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Discussion Starter · #28 ·
Do you mean the rotor is clunking against the wheel bolts? Did you find this out by shifting gear while jacked up without the wheels on?
no, i assumed this was the case by moving the rotor against the hub and noticing the size difference between the hub threads and rotor holes. i may have jumped to conclusions, but i was tired and frustrated at the time and decided to overdo rather than under do. this was possibly unneccesary
 

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Alright, to address what i can: el jefe, i bought the cheapo version off rockauto, rather than reman OEM. My fault, and old guy is just a patient at my clinic so not putting too much stock in what he says.

To the hub alignment dowel questions: I was thinking that there was enough slop in the lug holes in the rotor, that the rotor was clunking against the lug nuts when changing direction. After some thought (that wasn't immediately after wrestling with a somewhat taxing and definitely expensive driveway repair), I've come to the conclusion that I am... unsure. the clunk is gone. It used to occur when switching from P/D/R regardless of whether brake pedal was depressed or not. Could that have been a bit of play in rotor lug holes? yes. could it be play in the aftermarket cheapo CV axles? yes. do I know which? no. Do I think that there is some braking force applied to those alignement dowels? absolutely! how else would they shear off?

Am I going to unbutton everything, remove the jury rigged alignment dowels, button her back up and then test? likely no. If I do i will update. thanks for coming to my TED talk.
If you do open it up... (or if I have mine off for some reason, I will test a couple things)

You may want to inspect the rims to see if they look like they were loose at any point, which may leave a wear mark from the lug bolt on the rim. I can't imagine that properly tightened lugs wouldn't also pin the rotor to the hub. Even if some way it did move, it really couldn't clunk, it would move so slowly....

I have not seen alignment pins sheer off, but perhaps applying the brakes with loose lugs could do that? To see if that is even possible, you could remove the pins and put the lugs into the rotor and hub (just loosely) without the rim, and then see if you rotate the loose rotor by hand to see if sheering the alignment pins with the rotor is mechanically possible or if the lug would prevent that from happening. I suspect that a loose rotor (probably due to loose lugs) would still not rotate enough to sheer the pins. Maybe deform them, but sheer them? Seems unlikely, but until you try it, I'm just guessing.

If you take it apart, please take some pictures.

Also, I understand about the over-torgue situation. I have over-tightened every bolt or lug I have ever installed, except where it called for a torgue setting in a specific situation. I know this because after 48 years of tightening automotive parts, I started using a torgue wrench religiously, even on my oil pan drain bolt (since they do occasionally strip).

Looking forward to learning more about your situation at some point, the good news is - you fixed it! No more clunking.
 

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2016 3500 ext-ht
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If you do open it up... (or if I have mine off for some reason, I will test a couple things)

You may want to inspect the rims to see if they look like they were loose at any point, which may leave a wear mark from the lug bolt on the rim. I can't imagine that properly tightened lugs wouldn't also pin the rotor to the hub. Even if some way it did move, it really couldn't clunk, it would move so slowly....

I have not seen alignment pins sheer off, but perhaps applying the brakes with loose lugs could do that? To see if that is even possible, you could remove the pins and put the lugs into the rotor and hub (just loosely) without the rim, and then see if you rotate the loose rotor by hand to see if sheering the alignment pins with the rotor is mechanically possible or if the lug would prevent that from happening. I suspect that a loose rotor (probably due to loose lugs) would still not rotate enough to sheer the pins. Maybe deform them, but sheer them? Seems unlikely, but until you try it, I'm just guessing.

If you take it apart, please take some pictures.

Also, I understand about the over-torgue situation. I have over-tightened every bolt or lug I have ever installed, except where it called for a torgue setting in a specific situation. I know this because after 48 years of tightening automotive parts, I started using a torgue wrench religiously, even on my oil pan drain bolt (since they do occasionally strip).

Looking forward to learning more about your situation at some point, the good news is - you fixed it! No more clunking.
Just a wild guess, after all the work that was performed, but I would be taking a look at the motor/transmission mounts. Still doesn't explain how the clunk is now gone.
 

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2016 3500 ext-ht
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996 Posts
Or how the pins got sheared.
Strange, strange indeed. Somewhere down the line who worked on those wheels/assembly, buggered those pins, knocked them off and said, "good enough, send it".
I could imagine someone trying to fit aftermarket wheels. Locating pins may not have been in the proper spot. Collateral casualty.
 

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2017 Promaster 2500 159 HT Gasser
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Had my driver side CV axle go out 5 days ago at 105K miles. It went from no signs of problem to coming disconnected from the hub side and falling down in about 8 miles! It started as a vibration similar to road joints and got very noticable in 2 miles, pulled over, checked the boots, then limped 6 miles to a a repair shop at under 40 mph, it was really bad on right hand turns, went away on left.

I replaced the passenger side around 60K. It was a long time between occasional vibrations at the right speed, incline and turning before I replaced it, maybe 5k miles. I abuse the van on dirt roads alot but was surprised in how quick it failed on the drivers side.

The failure mode was likely a retaining ring on the hub end but never was able to prove it, the boots on both sides were intact until the hub side pulled apart on a somewhat tight left turn in the parking lot.

Finally, the ball joint connector on the hub is hard to clear the lower control arm (even with torsion bar unbolted) so I undid the top three nuts on the ball joint since you only need about 1 inch to clear those compared to nearly 3 on the bottom when I replaced the passenger side CV.
 
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