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Discussion Starter #1
I have a 2010 SE 3.5. I started hearing a low pitched knocking sound that was cyclical and dependent on rpm. I was really concerned about this so I looked on the forums and decided it might be rod knock. I got the oil tested and found 3x the amount of aluminum in the oil than typical so i decides to pull the engine. I tore it down down to to short block and nothing... Everything appears to be on spec. Crank end play, rod to crank clearance and the rods themselves have not play to make me think the bearing clearances are out. I cant find anything else wrong with the rockets or other areas... in running out of ideas on what is making the noise and wearing.

Does anyone have experience with this?
 

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The Bacon Hauler (‘12 Cop Charger)
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I have a 2010 SE 3.5. I started hearing a low pitched knocking sound that was cyclical and dependent on rpm. I was really concerned about this so I looked on the forums and decided it might be rod knock. I got the oil tested and found 3x the amount of aluminum in the oil than typical so i decides to pull the engine. I tore it down down to to short block and nothing... Everything appears to be on spec. Crank end play, rod to crank clearance and the rods themselves have not play to make me think the bearing clearances are out. I cant find anything else wrong with the rockets or other areas... in running out of ideas on what is making the noise and wearing.

Does anyone have experience with this?
You didn't happen to record the engine making the knocking sound did you? I realize it's a little late now to make a recording of it 'knocking', but if you made any video or sound recordings of it before you tore it down and can post that up somewhere for us to listen to, I think that would be the quickest way to get a consensus on whether or not it was a rod knocking (or other similarly fateful sound).

Absent that, I can only guess...your description sounds pretty dead-on though. Having a rod knock is certainly a unique sound, and if you've ever heard it, you will know it if you hear it again. That's what I'm getting from your post. So I will defer to you and agree, it sounds like the motor is toast.

As for why you could not identify the noise-making part once you tore it down, I don't know. I suspect it could all look fine and still make the noise; the only way to find the culprit might be to take the guts to a machine shop or something and have them take a look. Maybe they know some tricks of the trade for identifying worn parts where you may not. I don't know, that's just a guess...

Beyond all that, I do have the standard curious questions in such a scenario:

How many miles did the motor have on it?

Were you the original owner? If not, do you know how many owners it had before you?

Any significant events in its history that you know of, e.g. an overheating episode, almost running out of oil, etc.?
 

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The Bacon Hauler (‘12 Cop Charger)
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Discussion Starter #5
To the other questions, I am the third owner as of July 2014 at 48000 miles. I have 77000 on it now. I have done the oil changes at the factory specified intervals and never saw much of a problem other than the motor tends to need a bit added between changes. Nothing more than half a quart over the full interval but that is reasonable. The car has always been reliable and I have never had an issue before this. This car was never babied its been a DD since 17000 miles at least.
 

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The Bacon Hauler (‘12 Cop Charger)
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Unfortunately I did not record the noise, but this is pretty spot on to what I was hearing.

https://www.youtube.com/watch?v=zLdKZ-Kxvyc
AHHH, okay, you're still golden I'm pretty sure.

What you're hearing (well, what that Youtube video sound is indicating) is one or both of the rocker arm assemblies on the cylinder heads. The rockers are aluminum and over time will start to wear into the rocker posts they sit against, chewing themselves up and making weird noises in the process.

Check out this video for a visual of what I'm talking about (it has sound but wasn't recorded with the engine running, so you won't hear the knocking/ticking):


If that is indeed what is causing your noise(s), you only have to replace the rocker arm assemblies to remedy it. Unfortunately they are $250 apiece for brand new assemblies, but it's better than the alternative I reckon.

Anyway, if you're engine is still apart, you should be able to verify that the rocker arm assemblies are bad by physically checking them like I did in that YouTube video. If there's any play, that's your culprit!!
 

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The Bacon Hauler (‘12 Cop Charger)
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To the other questions, I am the third owner as of July 2014 at 48000 miles. I have 77000 on it now. I have done the oil changes at the factory specified intervals and never saw much of a problem other than the motor tends to need a bit added between changes. Nothing more than half a quart over the full interval but that is reasonable. The car has always been reliable and I have never had an issue before this. This car was never babied its been a DD since 17000 miles at least.
Yep, the mileage is just about right for the rocker arm assemblies to start mucking up on that engine, so I'm putting my money on that being the problem, not a rod or main bearing or anything catastrophic.

Also, regarding the oil thing, that's just something these engines do. I've found it's best to run a conventional 10W-30 weight motor oil (unless your location is too far north and won't allow that) as opposed to a 5W-30 or synthetic 0W-30. Mobil Super 5K is the best one I've found for not disappearing so quickly in these engines, but as long as you're running 10W-30, it will slow that down either way.
 

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Discussion Starter #8
Wait seriously? I wrote that off because every rocker on mine has about that that much of side clearance...
 

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wow- that's a LOT of side play...no wonder they'd make noise.
 

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The Bacon Hauler (‘12 Cop Charger)
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Wait seriously? I wrote that off because every rocker on mine has about that that much of side clearance...
Seriously...if you look really closely at the very edges of the rocker arm with play, you should be able to see really sharp curved edges where it's eaten into the post next to it. Slide the rocker arm over as far as you can so it is touching the post, and you'll see how it has eaten its way into the post over time. They are not supposed to have any space between the post and rocker arms, and if they do, they're going bad and should be replaced as soon as you are able.

Theoretically you could just keep running the bad rocker arm(s) for 10K or 20K more miles and not really notice any degradation in performance or anything. The noise would get worse, especially when colder temps are present at startup, but that's about it.

HOWEVER, you don't want to do that if you can help it. That aluminum material that is eaten away from the rocker arm and posts colliding is ending up in your oil and oil filter, but first it will get circulated around a bit before getting trapped.

That's less than optimal obviously. But even worse, if you let the rocker arms continue make contact with the camshaft lobes while operating all willy-nilly like that, it will eat up the camshaft lobes over time. And that's very definitely something you should try to avoid if possible!

Now having said all that and put the fear of god into you probably, I will say that if the rocker arm assemblies are "bad", you don't have to pawn your first born child to get the money to buy the parts to replace them asap. If you have to let it go 5K or 10K miles, you'll be fine. Just remember, ever mile you let it go, you're risking more wear on the rest of the engine further on down the road (like well past 100K miles and such).
 

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The Bacon Hauler (‘12 Cop Charger)
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wow- that's a LOT of side play...no wonder they'd make noise.
It would be an understatement to say the rocker assembly in that video "made noise."

At its peak, which unfortunately coincided with a very cold morning last winter, when I would start the car in the morning, I could expect to hear something akin to midgets trying to emulate the theme song to 60 Minutes by camping out in my valve covers and bashing the cylinder head with tiny ball peen hammers....

"PING, PING, PING, CLACK, CLACK, TICK, TICK, PING, CLACK, PING, TICK..." and so on for as long it took for the engine oil to get up to temp, which might be 10 minutes if I sat there and idled.

It was so disturbing even the wife chimed in with a "I think something's wrong the car..." a time or two :surprise:
 

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The Bacon Hauler (‘12 Cop Charger)
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In the interest of making sure I do not disseminate any bad info while trying to pass on the good info, I've broken my vow of silence and recorded a couple of vid clips for you hose-heads. Hopefully this will better illustrate how to tell if the rocker arm assemblies are bad, going bad, or still okay.

But I'll tell you right now, if you still have the OE set on your 3.5L engine, you will most likely have to replace at least one of them, and you'd be smart to do both just to save time and money. The dang things are crap and go bad, no exception evidently. Anyway, if yours are NOT making any racket right now, then you can hold off on doing anything to them or with them. But once they start to make racket when the engine starts up, you're on the path to replacement!

Visually checking the assemblies to see if they're bad vs. good:

Service manual info/details that will be useful if you do the replacement yourself:

There, now you can't say I never did nothing fer y'all!!
 

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Discussion Starter #15
Thanks Nuke. That makes me feel a lot more confident in replacing these and not tearing the short block apart. Do you happen to know the part number you ordered? I see 04892293AC but it is listed as 07 only. I'm looking at online retailers as the local dealership isn't competitive at $397/assembly. Any suggestions on a supplier?
 

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The Bacon Hauler (‘12 Cop Charger)
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Thanks Nuke. That makes me feel a lot more confident in replacing these and not tearing the short block apart. Do you happen to know the part number you ordered? I see 04892293AC but it is listed as 07 only. I'm looking at online retailers as the local dealership isn't competitive at $397/assembly. Any suggestions on a supplier?
Just saw this, let me find where I ordered mine and I can verify the part number.

As far as from whom to order, I went with a place I found on eBay (of all place!) that seemed to do a lot of business selling OE Dodge parts, oh yeah and that had good reviews. (Well, I didn't actually read a bunch of them or anything, but I did check to make sure they didn't sound auto-generated and that the place had been in business for a while and not some fly-by-night joint.)
 

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The Bacon Hauler (‘12 Cop Charger)
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Yeah, you're good to go with that part number you have.

I searched eBay again, and the available options appear to still be priced in the $250+ for one set or $500 for two sets range. And there's several Dodge dealerships' parts departments listed, which should be about as safe a place to order from as it gets for these.

Speaking of Dodge dealership parts departments, you should hit up Steve White motors to see if they can match the price of those other places listed in that search. They are a supporting vendor here, and I have yet to see someone post up a bad review of a transaction with them, so certainly nothing to lose from sending them a PM for more info.

One final thought on this subject: if cost of new assembly is too prohibitive, going used is an option. In fact, there is a place listed in those search results above that is selling used assemblies for $100. I will stop short of saying that's a great deal, as the possibility of getting an assembly that's already bad (but not yet showing signs of failure, e.g. like in my video from earlier) is at least 50% in my estimation, and then you will have to deal with pulling it back off and shipping back to them and waiting on replacement. That's a worst case scenario for sure, but if it does happen, the ROI of going used just vanished for my particular situation.
 

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Discussion Starter #18
Well the day is finally here... the motor is back in the car, the fluids are in and everything is torqued. Any suggestions on proper startup technique? The manual says run until hot so that's not really useful...

I primed the oil pump when I installed it, primed the oil filter, filled the block galleys from the rocker feeds in the head untill it bled out the other side and I'm still very nervous about starting. (I wish I could just run the pump with drill like the good old 318.)
 

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Beyond any pre-cranking advise you might get, you can use the method meant for a flooded engine to crank but not start, to get the oil pressure up. Press and hold the brake pedal, push the accelerator pedal all the way to the floor and hold it, then press and release the ENGINE START/STOP button once. The starter motor will engage automatically, run for 10 seconds, and then disengage. You could of course repeat that. Good luck. A Guy
 

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Beyond any pre-cranking advise you might get, you can use the method meant for a flooded engine to crank but not start, to get the oil pressure up. Press and hold the brake pedal, push the accelerator pedal all the way to the floor and hold it, then press and release the ENGINE START/STOP button once. The starter motor will engage automatically, run for 10 seconds, and then disengage. You could of course repeat that. Good luck. A Guy
You can also press and hold the Start button - don't run starter more than 20 seconds doing this. (windings heat up)

Let the starter cool for several seconds before trying the next start cycle.
 
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