I have a 05 dually 5.9l i bought the truck a few monthes ago and have been anoyed with these sound ever since.maybe someone has had the same noise and you could let me know what fixed it....1st is a swooshing noise that i can hear when im standing near the front of the truck,sounds like its right under the rocker cover at the front. 2nd is a slight detonation rattle, hot or cold under light acceleration,or cruising. a friend of mine has the identical truck and his doesnt make either if these noises. ANY ideas would be appreciated.Thanks.

 

its a diesel. the whooshing noise you hear is the massave fan moving air through the radiator, and the detonation noise is the 14 to 1 compression with fuel detonating driving the huge pistons down with great force.


the "fix" is to run it as hard as you can

 

Some trucks will make a little bit more engine noise than others, or more of a "timing rattle" type of noise. The CP3 pump is just a pressure pump with cylinders set up sort of like an airplane engine. If the CP3 "compression" is not in time with a cylinder injection, it can cause a "tick". There is a TSB for that. The "woosh" sound may be your fan kicking in, but a "woosh" can be many things... need to be more descriptive

 

Thanks but the swooshing sound is still there even when i remove the serp belt,that kinda rules out all accesories and the fan.it kinda sounds like a bad tensioner bearing but with that not spinning anymore it cant be.How is the inj pump timed?the other noise is still the one that bothers me the most,i know diesels run off detonation,but this is more of a ratteling sound,louder on the pass side of the truck,heard from inside.and goes away when it gets into boost or when i decelerate.

 

If I can make a suggestion.... go to your nearest parts store and purchase a mechanics stethoscope and it will assit you greatly in determining where the noises are coming from... under $20.00 dollars and a must for every gearheads toolbox.

 

did i forget to mention i am a 10 yr licenced transmission tech,im not just hearing these sound in my head,but this is the first diesel i have owned,and am not to familiar with the engine aspect of them.the noise i hear,i can not pinpoint.it seems to resonate through the front of the engine.