What's this pulsating sound?

[threejacks]

Scanner shows no codes. Noise started before: new waterpump and coolant, one idler bearing, new serp. belt, removed fan completely, still off, rebuilt injectors. Truck runs great, no misses in engine, tranny shifts smooth no problems.

hheynow It is 2 wheel drive dually. Like you I have had truck for 11 years and I know every sound it makes. TC has been rattleing for over two years or so. I know it's a matter of time on it.

 

[hheynow]

Scanner shows no codes. Noise started before: new waterpump and coolant, one idler bearing, new serp. belt, removed fan completely, still off, rebuilt injectors. Truck runs great, no misses in engine, tranny shifts smooth no problems.

Are you sure you're not driving my truck?

 

[MUDWHISTLE]

I don't detect this noise when under load. When I hear it most is steady and smooth, stereo off, smooth level road, cruise control on(steady rpm). Everything has to be very quiet, it is not very loud but concerning.

Yeah so if you don't here it under a load it could be your turbo cause it would be spinning at a higher rpm due to the truck pulling harder creating more boost and not running in the rpm range thatit is when you empty.-popcorn

 

[hheynow]

Update. The sound is still there. Scanned my truck and came up with 0334 (bad CPS) so I thought the noise was cam related. Put in my spare CPS and the code cleared by the noise was still there. Now I'm thinking it's a cupped bad tire. I'm due for my free rotation soon so they will put it in 4WD on the rack and visually check for bad tire wear as all tires spin.

 

[threejacks]

I hope you find something. The only thing about tires is that my truck was making this sound with worn out tires. I have replaced all 6 since this noise started.

 

[hheynow]

I think our trucks are cursed with gremlins.

 

[95_stroker]

Now I'm thinking it's a cupped bad tire.

See post #6.

 

[hheynow]

See post #6.

Mike, I thought of your and Kevin's reply when posting, but the verdict is still undecided. The tires have 47K on them, but still have plenty of tread left. If it turns out to be the tires then I'll calm way down. It's engine/drive train problems that would worry me more.

 

[95_stroker]

Mike, I thought of your and Kevin's reply when posting, but the verdict is still undecided. The tires have 47K on them, but still have plenty of tread left. If it turns out to be the tires then I'll calm way down. It's engine/drive train problems that would worry me more.

I know the sound you are describing, I have it as well, I just choose to ignore it. I too hope it is only tires on your rig.

 

[BJS]

hanger or midshaft or driveshaft bearing which ever you want to call it are quite notorious for causing noise but will only do so when under load not when you're just coasting.