• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Why does a 6.5 sound weird

Chevy3500

Chevy3500

New Member
Messages
198
Reaction score
1
Location
Sunbury, ohio
Its hard to explain and im not sure if anyone else can tell but why does a 6.5 diesel not sound consistent, they run smooth but its like you dont hear the same sound from the engine more than once, im not talking about the exhaust im talking about the engine, a cummins the engine sounds the same, im talking at idle, i will post a vid of a cummins and a 6.5 and it seems like its the topend that sounds different, just listen to them and see if you hear what im talking about and no im not weird, just something i noticed These arnt my trucks and the sound reminds me of steel balls in a can in the 6.5

:mad2:http://www.youtube.com/watch?v=VopjI2nbENw&feature=related

http://www.youtube.com/watch?v=_W4vlP8xZGQ&feature=related
 
The differrences you are describing is teh differrence in sound between a direct injected diesel and an indirect injected diesel. If you listen to a 6.9/7.3L IDI they sound like the 6.2/6.5 does.
 
I have heard a few cummins and some idle loud whereas others idle much quieter and they are the same years. Might be that some have turned up the timing. Even on new diesels they are so quiet and that is accomplished by pilot injection. It is like a double squirt of diesel on each compression stroke. Technology has made it possible to even have ever cleaner burning diesels. It's the old mantra, you learn something new every day and engineers are working to overcome obstacles here and there.
 
Pilot injection is huge at quieting a diesel clatter.

Older Cummins have more clack. I think some of the 6.5 clickety comes from V8 harmonics coupled with IDI and IP on top in V of engine. The Stanadyne IP's are more clickety sounding. I think its the plungers and cam ring clicking and resonate in V of engine. Cummins is also a longer stroke diesel so at idle low fuel you don't get so much pop at top of stroke (this is also due to DI vs IDI). Again pilot injection is huge at quieting the nailing at top of stroke combustion.

Sound is personal preferance I like the 6.5 rumble and many Cummins sound good to me. Except the BLAP BLAP BLAP noise of some oversized exhausts. I like the sound of my John Deere, and Ford tractors. I like the sound of Kubota, Deutz, and Yanmar tractors too. Of all the Diesels I least like sound of the a 6.0 Ford. I think its the injectors sound I don't like. It has a TINK or too much click sound to it IMO. Its a louder slower click sound than the stanadyne IP's that the combustion doesn't rumble over and cover up. Ford's tend to have a different starter sound too for some reason. Mostly its what ever you get use to and like.
 
I love the sound of diesels and cummins and powerstrokes, its just like the 6.5 engine noise is so different its never the sound is never the same like the cummins
 
You must log in or register to reply here.
Back
Top