Engine Clatter, and Rough Idle.

[Rowdy Dalton]

My 2006 2500 has always been a noisy engine. But, over the years, the Lifter Clatter has been getting worse. At about 120,000 miles, I had the valves adjusted, at a Cummins Repair site in Houston. It really didn't help much. When I would put fuel additives in, that were lubricity and Cetane boosters, this helped with it a lot, under acceleration. But, not completely. The idle was rough, and noisy. It got worse when it basically sat for 4 years, and was driven very little, every 3-4 months, or when I needed to haul something for the yard/house.
I'm using an oil additive and a recommended fuel additive, thinking there has been carbon or sludge built up on the lifters. So far, so good. But, I just put it in, a few days ago, and did about 9-10 hrs of driving. Time will tell.
Have others had similar issues with an excessive amount of engine noise, with a rough idle?
Wht was done to fix it?

 

[AH64ID]

As I mentioned in the other thread your 06 uses flat tappets, so no lifter clatter.

It’s possible you have some injector issues after that little driving.

The 06 ECM also doesn’t seem to fire the injectors as smooth as other ECM’s of the era. It was a new ECM in 06, and I don’t think they got the drivers as precise as they could. Above idle fuel it they smooth out, but I’ve been around several 06’s that are just rough at idle… even in balanced rotating assemblies.

I also mentioned in your other thread that oil additives aren’t a good idea. Running a quality oil without additives is a much better idea.

 

[Darkbloodmon]

I was just about to say its a flat tappet pushrod engine, there aren't any lifters.

Injector knock can sound like lifter tap/clack, I'd look into your fuel system.

How many miles are on your truck and are the injectors original?

 

[Rowdy Dalton]

186,500 give or take. I know that over the years, even when I drove 70+ miles a day,.the clatter would get worse, over the years. I know that adding Cetane Booster quieted the injectors a lot. i know that I regularly change the oil, and have used quality oil, mostly synthetic, for the last 100,000 miles. I also know diesels are notoriously dirty engines, because of the nature of a diesel engine, so over time, things get dirty. I do know that adding this particular oil additive has made an audible difference. It also feels smoother, from idle to acceleration. But, what do I know, I've only driven 186,500 miles with this engine.
The fuel additive is supposed to unstick and clean up injectors. Time will tell, especially when I stop using the product.

I have not torn this engine apart, so I don't know where the internal issues are, when miles start racking up.

..

 

[Rowdy Dalton]

Oh, in my older diesel truck, many years back, I would dump old and filtered vegetable oil into the fuel tank. It ran just fine, with a gallon or two of veggie oil per tank full. It made the exhaust smell like French fries too.
I also filtered my used motor oil, and put it into the tank.
I wouldn't dare do this with a Common Rail Injection system.

 

[AH64ID]

Clatter or timing rattle? One is common, the other isn’t.

On these motors if an oil additive makes a difference then something is likely failing internally, which isn’t common for oil lubricates components of this engine. Nothing on these engines should be quieter with an oil additive (no HPOP, no hydraulic lifter, etc), so I’m inclined to think you wanted to hear a change so you did.

Cetane boost does have its place, mainly in low load and low rpm applications. I use it when I won’t be working the motor hard and want to help ensure complete combustion. That being said my stock 05, which was basically the same as your 06, hated Cetane boost. It made it sound like it had a rod knock, but once I put better pistons/injectors in it I could
run some Cetane boost when the conditions are warranted it.

You thought the engine had hydraulic lifters, so the miles you’ve driven in it seems irrelevant to what you may or may not know about it.

 

[Rowdy Dalton]

Clatter or timing rattle? One is common, the other isn’t.

On these motors if an oil additive makes a difference then something is likely failing internally, which isn’t common for oil lubricates components of this engine. Nothing on these engines should be quieter with an oil additive (no HPOP, no hydraulic lifter, etc), so I’m inclined to think you wanted to hear a change so you did.

Cetane boost does have its place, mainly in low load and low rpm applications. I use it when I won’t be working the motor hard and want to help ensure complete combustion. That being said my stock 05, which was basically the same as your 06, hated Cetane boost. It made it sound like it had a rod knock, but once I put better pistons/injectors in it I could
run some Cetane boost when the conditions are warranted it.

You thought the engine had hydraulic lifters, so the miles you’ve driven in it seems irrelevant to what you may or may not know about it.

You might be right.

 

[06 Dodge]

When I had my 06 I noticed that the injectors were louder when it was not being drives very much, the only real cure was 6 oz Lucas in the tank and a nice 4 hour drive with 700-900Lbs in the bed, after a long drive injectors had a lot less noise and you could once more hear the turbo sing it was so happy...