Engine/Transmission (1998.5 - 2002) what makes our engines noisier than 2003 an up

[GreggNoble]

. hi ,i love the sound off my old 2001 24 valve, i`m thinkin on buyin a 2006 now but i wish it sounded like my old 24v (now the girlfriend has a quite different view) ha ha ha

i always thought that it was just beter insulation between the cab and the engine, but no, there is far less noise commin from the 3rd gen engines. what accually causes this? i done seeany insulation on the engine itself? thanks

 

[Grizzly]

It has to do with the High Pressure Common Rail system of delivering the fuel to the cylinders. I know it sounds like Greek, but for some reason, that's why. I hope someone with better knowledge will chime in here. This is a system that Dodge picked up from Mercedes when Chrysler was married to them.



I have no idea how Furd quieted their sick o engines, which are still louder than Dodge.



I too loved the sound of my 95 CTD, but after I got used to the 05's quietness, I like being able to talk to someone standing outside my truck while the engine is running. Wish we had a switch where we could turn it off and on.



george

 

[GreggNoble]

ha ha h, yea, i like the looks i get when i pull through a drive through window,i do have to shut it down too. yea, i`d like to understand what the difference is hope someone can elaborate on the fuel delivery system,thanks

 

[JCyrbok]

ha ha h, yea, i like the looks i get when i pull through a drive through window,i do have to shut it down too. yea, i`d like to understand what the difference is hope someone can elaborate on the fuel delivery system,thanks

my understanding is that with the common rail injectors and the CP injection pump there are several smaller injections of fuel into the cylinder instead of just one big one at TDC'ish.



J-

 

[GreggNoble]

sounds interesting, its amazing that the timing isn`t affected by that

 

[Wyomingcowboy]

my understanding is that with the common rail injectors and the CP injection pump there are several smaller injections of fuel into the cylinder instead of just one big one at TDC'ish.



J-

From what I understand, this is correct. This is also the cause for lower mpg's.

 

[cerberusiam]

Multiple injection events that keep cylinder pressures at a usable level with no big spikes to create the hard knock. Also, multple injection events mean multiple combustion events. Timed correctly the "bang" of idividual ignition is dampened by the effects of the following event.



Injector spray angle, piston bowl, and the general combustion event all help to reduce noise. The engine block itself was also redesigned with heavier materials in the areas that transmit the sound.



Timing is not effected by the events, its key to making the events work correctly. CR engines are retarded much more to meet emissions but it also helps to keep noise levels down. Timing is the key to making the power levels they do, meeting emissions, and still making a quieter engine.



None of this technology was "picked up" from Mercedes. Dodge buys the engine as a unit from Cummins with the fuel system already their. The Bosch High Pressure Common Rail has been used on just about all diesels engines built in the current era. It is used because it is the best of the crop at doing what it does. Cummins has used Bosch fuel systems from the time they started providing engines for Dodge, just a shade over 20 years, and the HPCR is natural prgression. Isuzu and I believe even the new Fords all use the same HPCR systems and multiple events to meet power and emissions levels.



Contrary to popular belief the fuel systems have nothing to do with mileage. In fact, an HPCR system in a comparable 24V motor is probably 20-30% more efficient than a jerk pump system. The facts are the newer trucks are heavier and more powerful than ever and, even hampered by emissions, the mileage is still routinely as good or better than earlier models. Pound for pound, mile for mile, a CR is on a par with a 24V in efficiency and a whole lot cleaner in the exhaust emissions arena.



Just wait for the NEXT geenration of fuel systems to become common. Injection pressues in excess of 30k psi, up to 9 events in an adaptable configuration, piezo injectors capable of activating 9-11 events in less time than a single jerk pump event.



Nullum gratuitum prandium, the price we pay for progress.

 

[n7gxz]

Also a lot of the noise is from the VP44. The injection pumps will create almost as much noise as the engine itself.



The block between the 2nd gen, 3rd gen, and 4th gen have had some internal redesign work done to stiffen and quite down the engines.



Kevin

 

[GreggNoble]

i hate hearing a diesel engine and not being 100%sure that it is a diesel, i think they should have just insulated the cabs beterand let the engine keep its masculin roar ha ha ha ha thanks guys

 

[Midnite]

Aren't they using double wall valve covers and oil pans too? Can't remember where I heard that one.

 

[CSnyder]

Change out the exhaust manifold to the 2nd gen style and you will get the 2nd gen sound back. Ive done several of them like that.

 

[WestTN]

One injection shot versus several small shots.

 

[PC12Driver]

Pilot injection

The missing rattle is mainly due to a small squirt of fuel ahead of the main injection event. From Edmund's Inside Line:

"Pilot injection — Sometimes called "pre-ignition," pilot injection eliminates the combustion spikes that cause the "rattle" traditionally associated with diesel engines, especially at idling speeds. Pilot injection introduces a small quantity of fuel into the combustion chamber prior to the main power-inducing explosion. This injection takes place within a few ten-thousandths of a second of the main explosion and results in a smoother combustion cycle and reduced clatter. Even at a standstill, an Audi, BMW or Mercedes-Benz diesel is now all but as refined as its gasoline sibling. "​

If you've ever been in a Powerstroke 6. 0 you can hear it turning on and off. The engine will sound like BBs dropping on a pie tin when the pilot injection turns off. I haven't really heard much of a difference in the common rail Cummins engines though.

 

[Vaughn MacKenzie]

Actually on the early common rail engines there was only 2 injection events, the pilot then the main event. 3 injection events started on the 04. 5 engines, the pre and main events, with a post event late in the combustion stroke for emissions purposes. I'm not sure how many injection events they use on the 6. 7 though.

 

[Midnite]

Reminds me of the disposable razor skit on early Saturday Night Live from the 1970s:

"The first blade lifts the whisker, the second lifts it a little more, and the third rips it right out by the roots!"

 

[GreggNoble]

would be great if you could turn off the multiple injections when the wife wasn`t in ha ha ha

 

[Ncostello]

It's my opinion that the injector pump on 24V and other pumped engines create much of the "diesel rattle" or noise you hear. If you've ever been in a pump test room when they are testing one... you'll understand. If you were taken in there blindfolded... you might believe the entire engine is right there running. Its suprising. Since CP3 common rail pumps are just high pressure fuel pumps supplying constant pressure to the rail... you don't get the injector pump timing noise. The common rail injection at the injector is a much quieter process... especially with pilot injection to "start" the combustion process. The combustion stroke in the cylinder itself isn't all that loud except out the tailpipe if you have no muffler. Not way more than a typical big block gas engine "bang". A Duramax under load sounds much like a big block gasser at the tailpipe (except the turbo noise). To me anyway.



Now... you can make a common rail sound more like a 24V I believe by reducing or removing pilot injection. Thats why 6. 0L Fords were originally very quiet... then got loud once Ford basically eliminated the pilot injection in the programming. A 6. 0L with no pilot injection is a pretty loud engine. Except thats not HPCR... its oil hydraulic system... which an entirely different theory... one they don't use anymore either.

 

[Fireman Dave]

It's my opinion that the injector pump on 24V and other pumped engines create much of the "diesel rattle" or noise you hear. If you've ever been in a pump test room when they are testing one... you'll understand. If you were taken in there blindfolded... you might believe the entire engine is right there running.

Yup - exactly. I believe the VP44 pumps are a bit louder than the P7100 pumps on the 12 valvers, too.

 

[dcoffman]

Those BB's dropping on a pie tin are the guts falling out of the 6. 0.

 

[GreggNoble]

there is no way to turn off the pilot injection system on the 2003 up engine is there?

i love the sound of my 2001 almost as much as i hate the front end ha ha ha ha

it doesn`t just start up like a ford or duramax , it springs to life with that crackling "eager to work" sound that i tell the wife is so masculin that she isn`t supose to like it ha ha ha and when i`m pulling in the drive way of the local day care our little 2 1/2 year old daughter hears me at 100 feet away and knows it my truck and yells "daddy daddy . thinkin on gettin an 2006 but i`m sure gonna miss that 24valve.