3.6 Pentastar Rattling

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vames

vames

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Hi. I drive a 72 Swinger, but I have a question about my other car -- 2014 Town & Country 3.6 with 115k on it.

Six months ago, the battery light came on and the battery went dead. It was the original battery (!) and the alternator was bad, so I got a new battery and swapped the alt with a rebuild from NAPA. Three months later, the alternator was making a whirring/whizzing noise -- no batt light and it was charging. I pulled it and got a warranty replacement from Napa. Another three months and it's making a rattling noise now - again, no dummy light or code - just noise.

Am I missing something or am I just unlucky or does Napa just sell garbage? Whirring and rattling are two different symptoms!

I have the day off tomorrow and I want to take care of this and I don't want it to happen ever again. I don't think Napa will give me my money back - just a replacement.

Do I install it?

Do I eat the $350 I gave Napa and go to the Chrysler dealer parts desk and pay what will certainly be $600+ for OEM?

Is there something I'm overlooking -- could a bad belt or tensioner be somehow eating alternators?

I appreciate the advice.
 
Well crap. I swapped out the alt and that wasn't what is making the sound this time.

Then I took the serpentine belt off and started up the engine, and sure enough the rattle is still there. I fear this poor beloved van has something wrong that's not worth fixing. I might be heading to the Chrysler dealership to get a new Pacifica soon.
 
I think the only thing left turning on the front of the motor without the belt on is timing chains and cams. If its whinning with the belt, the power steering resevoir has a screen that will plug up, you can clean/replace it and that helped quiet ours down a bit.

i just did timing chain job on my then 173k mile GC the week before a 3600mile vacation. Its not "Fun" but it was pretty strait forward, plus i was able to pull cams and inspect every rocker, but thats more of a "ticking" sound when they are bad. Cams and rockers were about as perfect as could be though I suspect I might have just been lucky and/or good oil. Your timing chain cover is probably leaking and that will eventually burn up an alternator and/or its clutch. If you havent done a oil cooler, this is when you would buy that aluminium dorman replacement. Also time for water pump, Tstat, and trans service...

Cam chain guides will make a particular sound when they start to get sloppy. So much that i heard an engine start up and without looking you just know its a pentastar with some miles. Our van is noticiably quieter on startup though i also used 5w30.
 
Thanks for the feedback @Trojmn. I might take it to my trusty local mechanic to ask him what's wrong with it, but I'm not prepared to spend much on a 115k mile T&C.

Much more inclined to go down to the dealership and buy a new van (not sure whether I'd go with a Chrysler or a Toyota). This is what I haul my kids and family around in -- I want zero trouble.
 
Could be the roller lifters on the 3.6. Those are notorious for going bad. If left they take out the camshafts. Unfortunately pretty common on those. Changing the lifters isn't too bad, done it myself. But changing the cams is a new level because of the timing chains. I think they make a tool to hold the phasers in place and allow you to remove the cam.
 
kb67mopar said:
Could be the roller lifters on the 3.6. Those are notorious for going bad. If left they take out the camshafts. Unfortunately pretty common on those. Changing the lifters isn't too bad, done it myself. But changing the cams is a new level because of the timing chains. I think they make a tool to hold the phasers in place and allow you to remove the cam.
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I didn't know you could change the roller rockers without taking the cams out.

FRT the $20 amazon tools didn't help me any at all. I did it 'wrong' about 20 times until I had one extra hand to hold the chain on the lower sprocket. IMO if it has 100K miles on it and you have it open, id change the 2 big chains and the intermediate chain and tensioners. I didn't bother with the oil pump chain (its very short/pita to get off) and my van had 173K miles on it (I owned it since ~40K)

Total parts was $661 that includes timing chain, full set of engine gaskets, water pump, 8 rockers i didnt use, and trans filter.
 
vames said:
Thanks for the feedback @Trojmn. I might take it to my trusty local mechanic to ask him what's wrong with it, but I'm not prepared to spend much on a 115k mile T&C.

Much more inclined to go down to the dealership and buy a new van (not sure whether I'd go with a Chrysler or a Toyota). This is what I haul my kids and family around in -- I want zero trouble.
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I was in the same boat as you and was dreading taking the van with the whole family on a long trip. I was oogling Pacifica's to replace it. Once i tore into it and saw how great everything was internally I'm way more confident in the well maintained van i know than some unknown, besides ALL dealerships have busy service bays. Also 115K miles isn't alot.

Other thing besides the rockers eating cams to look out for:
Oil cooler ~$200 for the dorman aluminum one
Heater y pipe/hose (right by master cylinder) it gets hot and leaks ~$20
T-Stat I'm on my second ~$15
rear air lines ~$100 for aftermarket
 
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@Trojmn, you make a compelling point -- its just a car and it can be fixed! But somehow I'm not as motivated to dig into a 2014 minivan as I am to dig into my 72 Swinger. ( Not that the 72 ever needs it -- its ridiculously reliable.) I just have to figure out what exactly is wrong with the van. Changing a alt or a tensioner is one thing -- opening the engine is a whole other thing.

I took this video in which you can hear the sound. It doesn't "feel" like it's the valve train -- power smooth, idle is smooth -- its not super rhythmic -- it's more of a rattle. NO check engine light and NO codes.

 
* My last tank and current tank of fuel are E85. I cannot imagine that would be responsible for this, but worth mentioning.

* If it were a loose/busted lifter, wouldn't I be getting a dummy light or code?

* If it were the oil pump, wouldn't I get a be getting a dummy light or code?
 
At this point, it seems certain that one of the timing chains is knocking around in there (maybe due to a failed tensioner or guide?). The chain obviously hasn't broken yet (it runs smooth and no code).

I'm not going to attempt this myself, so I'm going to bring it to a mechanic tomorrow to see what he quotes me. That will determine whether I go get a new van or fix this one.
 
vames said:
At this point, it seems certain that one of the timing chains is knocking around in there (maybe due to a failed tensioner or guide?). The chain obviously hasn't broken yet (it runs smooth and no code).

I'm not going to attempt this myself, so I'm going to bring it to a mechanic tomorrow to see what he quotes me. That will determine whether I go get a new van or fix this one.
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The 4.0L that briefly preceeded that mill were notorious for the crank dampner letting loose & slipping/rattling, which caused drive belt issues, etc.
The cam actuators could be bad, or starved for oil for some reason, plugged passage dirty/clogged OCV's etc.
It almost sounded like it was louder Dr. Side tho', I may have missed, does it vibrate on revving?
 
If there are no pending codes, I doubt it's cam controls, there should be a CMP/CKP Sync fail code in the chamber for one of the cams if so.
 
Just to close this one out -- this was a cracked flex plate (or flywheel as we call 'em). I had it replaced by a very experienced transmission guy. Not cheap but I'm sure I'll get another few years out of this van.

Apparently these flex plates are a known issue in the Gen5 chrysler vans. In my case, the center where it bolts on had a complete crack around it, but it remained in the same plane as the rest of the plate, thus the car was driving fine and not throwing any codes. It was just rattling around in there.

Apparently this was a well known issue with these 3.6 Pentastar/62TE transmission combo.

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