Another Slight Knock Thread - At Idle When Warm

[scnautique]

Hey all. I just picked up a 2012 1500 with the 5.7 (this is now my third 4th gen truck lol). I will tell you that it is incredibly hard to find ANYTHING else other than the 'Hemi Tick' and the exhaust tick issue when searching through the forums and Google so sorry in advance for yet another knock/tick thread about the Hemi.

I will say that I am very familiar with these trucks. Two out of three 4th gen trucks that I have had now have done this to some extent at idle - it's a slight knock and a tad bit of a rough idle. My 2013 did it (bought it used with 20k miles), my 2014 did Not do it at all (bought that one brand new and maintained it myself till about 60k miles) and now my 2012 does do it (bought used with 85k miles). It is not manifold bolts or an exhaust leak, I just had all manifold bolts replaced and have dealt that problem multiple times on these trucks so I'm positive it's not that.

It only seems to really happen below about 800-900RPM, and worsens the lower the rpm gets. I've done pretty much everything I have been able to find on the Forums - I'm running Pennzoil platinum with the rated weight and Mopar filter in it right now. Just added Lucas oil stabilizer too. I've also cleaned the throttle body, replaced the intake related sensors including the PVC valve (I was thinking that the slight shake was coming from a vacuum related issue), did all of the spark plugs, ran 91 octane - no luck. No codes or anything. Truck kinda shakes a bit at idle too. Appears to be coming more from the driver side fenderwell area than the passenger.

Anyone else's truck do this? Any suggestions? Runs great, plenty of power - I just put 600 miles on it and towed a heavy load about 100 miles with no issues. Noise hasn't gotten any worse or better.


Here's a video I found that is very similar to what I'm hearing. Any input/experience appreciated!

 

[Burla]

Lifter tick, but it's running rough so it there a mis fire?

I wish you woulda asked before dumping lucas. But it's too late, now let's see how it is a couple days.

 

[indept]

Just curious, why did you go from a 2014 with no issues to a 2012 used?

 

[Burla]

We have found a legit cure for hemi tick here, however it has a much less success rate on vehicles over 75k miles. And the running rough suggests cam damage, not proves cam damage, just suggests it when added to hemi tick. Cam lobs that die from hemi tick seam to be most prevalent 70k miles to 130k miles, that was the range set by the other ram forum that has done good work polling this issue. Our forum has done good work on the fix.

 

[scnautique]

Thanks guys for the quick responses.

Lifter tick, but it's running rough so it there a mis fire?

I wish you woulda asked before dumping lucas. But it's too late, now let's see how it is a couple days.

I've seen some folks have had good results with lucas. Are you suggesting it'll do more damage? I've put enough miles to tell whether it would have an impact or not and I would safely conclude that it has not had any impact to the noise.

Also, there are no codes and the slight vibration/knock/tick is consistent once it drops all the way down to 550-650 idle rpm which I feel like would rule misfire out?

We have found a legit cure for hemi tick here, however it has a much less success rate on vehicles over 75k miles. And the running rough suggests cam damage, not proves cam damage, just suggests it when added to hemi tick. Cam lobs that die from hemi tick seam to be most prevalent 70k miles to 130k miles, that was the range set by the other ram forum that has done good work polling this issue. Our forum has done good work on the fix.

Thanks Burla, which thread is the legit cure for the tick, redline oil? And so you're suggesting this is the hemi tick + cam damage which will eventually lead to cam failure? Only way to verify this would be to pull it open and look at the cam I'm assuming? Also i wouldn't say it's rough but for someone with OCD you'll notice a very slight vibration at idle. I can only say that this isn't normal because I've had two other identical trucks. I figured it was a small vacuum leak to be honest which was leading to a lower/rougher idle which was causing some abnormal noise.

By the way, is there a particular hemi tick thread that defines your understanding of what it is? I swear I've seen many versions and different opinions and at this point I don't know if it's valve, cam, lifter, fuel or exhaust leak related so just wanted to confirm we're talking the same thing. This topic has been over-covered..

Just curious, why did you go from a 2014 with no issues to a 2012 used?

Let's just leave it at it was a mistake and I wish I could go back in time..

 

[Burla]

redline tick poll

lubegard tick thread

lubegard versus mos2

Lucas is an oil thickner, end of story. It may help, but the same thing can by achieved by going up in weight. But, as stated with as many miles as the truck has, it is more of a crap shoot. You can read how successful those products were. Now, moly takes time to plate or have the plating effect, so if you try it keep in mind it might take a while. You could dump 15 ounces with your current change, would be a good idea imo. It is thinner then 5w20 a little, but it sticks to metal.

The back of those tick threads has the answer to what is needed and the condition of oem metal. It does state the cause, but clearly the cause is lack of lubrication. The parts themselves are fine, the metal is top shelf.

 

[scnautique]

Thanks @Burla . I think i'm gonna give the Redline 5w-20 a go and test her out. Since I already added the lucas additive, figured it'd be better to start fresh with redline before stacking a second additive. Not sure how those play together.

If she still is making noise, i'll add the lubegaurd 15oz and see how it does

 

[indept]

Chances are if it happens when the idle drops its the lifters. Oil pressure drops from about 50 psi to 30 psi once engine speed is below 900 rpm. The Redline should help.

 

[Burla]

Thanks @Burla . I think i'm gonna give the Redline 5w-20 a go and test her out. Since I already added the lucas additive, figured it'd be better to start fresh with redline before stacking a second additive. Not sure how those play together.

If she still is making noise, i'll add the lubegaurd 15oz and see how it does

Wait please...

So I wouldn't have recommended lubegard with the lucas already dumped in w/o considering both formulas. So they are compatible.

We don't know for sure if redline and Biotech are compatible and Redline doesn't recommend additives. When it comes to redline or lubegard, it would be my opinion to use one or the other. The potential issue are the esters, both formulas have esters, and there is a maximum allowable ester %. Now, I do believe both products would be well under that number, but it still is a "potential" risk.

Now, there would be much less chance of 5w20 redline working in an aged hemi, I really would use 5w30. When the tolerances raise with that much use, you really should go up in viscosity even more then in newer rams, and we still use 5w30 redline in newer rams with low miles.

 

[scnautique]

Thanks @Burla .

So knowing that I added the lucas oil thickener, do you think that it would somewhat mimic the viscosity increase that you're suggesting with the redline 5w30? Or do you still think it's worth giving redline 5w30 a try.

I'll switch my approach around and try the lubeguard first with the existing pennzoil 5w20+lucas that's in the truck now (fresh with only 5-600 miles on it). Then, depending on your input if that doesn't work i'll try the redline 5w30

 

[Burla]

Since the lucas deal is fresh and new, I would roll with it for at least a little while. What I want to know is did this change at all, even a little better or worse? If it is lifter tick, then doing this should have changed some of the tick's cadence. So I think you should have a oil level just above full line, if you have to dump a little out, so be it, and then dump in 15 ounces of biotech. Again, what I am looking for is any change. I would expect some change with biotech added to lucas. You want a total of 7.5 quarts in the sump after you add the additive. Which is 7 quarts whatever, plus the biotech.

If you did this and there was no change in the tick, my guess would be redline probably wouldn't help. That either the tolerances are too large that lubrication can't solve it, or that it is something different.

 

[scnautique]

@Burla ok i'll run with the lucas additive until I reach 1k miles on it. I'm at about 600 miles on it so far and nothing yet.. I ordered the biotech so it should be here in the next few days and I'll try that once I get a few more miles on it.

My hope is that oil will be able to resolve it... but in the case that the tolerances are too high or there's another underlying problem, are there other easy things to check off the list here related to vacuum leaks or other known issues that would drop the idle down into the 500s and cause the noise in the video and a bit of roughness at idle?

 

[Burla]

Fuel issue? Take off air filter while at home and let the air just flow, rule out air. It can't be plugs or coil pack or you would get a code.

 

[ChevySlayer69]

IMO it's piston slap based on that example video and you describing it as a knock only at low rpm

 

[scnautique]

@ChevySlayer69 the only reason i'm questioning that it's piston slap is because it doesn't go away at all after it warms up like many of the threads I've read. That said I'm no mechanic so I don't know if the fact that it makes no difference to the noise necessarily when it's warmed up. It happens as soon as the truck drops down into the lower RPMs and it's sitting at around 600-650. Sometimes drops down into the 500s.

 

[scnautique]

@Burla Here's a video from underneath my truck this morning after letting it run/drive for about 5 min. Sorry it's dark. The video starts a little in front of the oil pan on the driver side, moves behind the pan, then to the passenger side of the motor (where you see the light through the fenderwell) and then back over to the driver side near the exhaust manifold area where the knock is most present in my opinion. I think the end of the video is most telling where the camera is near the manifold.

Again, I just changed and torqued the exhaust manifold bolts and it had no impact to this noise. It's not an exhaust leak (just have to say that again for new folks reading the 2nd page of the thread).

 

[Burla]

Your hemi ate the same sewing machine many of us has. Let's see what lubegard does.

 

[scnautique]

Should I be worried about reliability?

 

[scnautique]

@Burla how long did it take for you to start to notice a difference after adding lubeguard?

 

[14Deebo]

Sounds very similar to my 2014 with 50k miles, that recently had a failed lifter. Eventually it caused the valve spring to break which caused the rough idle and eventual misfires.

I would plug an OBD scanner and see if you get any pending codes. I believe there has to be several warm up cycles in a row with a failure to actually throw a code. I would be interested to see if you have any pending misfire codes or not. To me it sounds like a it may be a stuck/failing lifter, and eventually that will become a huge problem if it starts eating into your camshaft and starts cycling metal shavings through your motor.