I've got a hum especially noticeable between 50-60mph. Mostly notice it when foot's on the throttle. Not loud enough to drive you crazy, but it's there. Seems as though it sort of pulses, rather than a steady sound(rises and falls). Any info., suggestions...

 

Teach it to sing???? (sorry couldn't resist)

Do a search. Tons of info here.

 

Took it in to the dealer. I had pointed it out at 1000mi. They said it was "normal break in sound for that rear-end. Took it back at 5000Mi., and they said the same thing. My brother has an '03 SO with same rearend. His had no sounds like these "ghosts". I'll wait until about 10000mi and take it to another dealer.

 

I have a 96 2500 gaser that had the same sounding problem. I took it into the dealer & they found my axel bearing closest to the pumkin were going out. They cought it before it wore through the axel tube. I still needed to replace the rear end.

 

Thanks Cummin '01. They don't want to do anything about it obviously, so I'll let it "break in" a bit more. I've only towed my fiver about 800mi. so far, and I sure don't want it to go on vacation this summer, especially on the hills I'll be pulling up and down!

 

I have noticed a cyclic hum as well. Kind of like: hummmmmm ____________ hummmmm ___________ hummmmm. Can't say that I know where it is coming from. Doesn't seem to be from the rear. Feels like engine/tranny vibes. Truck has 2,400 miles on the clock. Not a big deal yet, maybe it just needs to break in more.

 

Mine seems to do that also kry. Especially at speeds between 50-60mph.

 

I noticed mine at 70mph. Don't drive too much at 50-60.

 

I hear what you're saying. My last truck was the GMC 6L gas-guzzler. It had pretty good pickup unloaded, and I wasn't sure my Cumins would match it empty. I was wrong. It's really hard to hold the CTD back. (When wife is with me, she keeps harping about getting a ticket. I last had one back in '81, but with this truck it might not be much longer!)

 

Mine does the same thing, I am leaning towards maybe the Turbo, becouse when its doing it I can floor it then it goes away!

 

Yeah, I am also leaning towards the turbo making a lot of the noises we hear. This morning I thought I started to get the rear-end howl, but I reved the engine at a stop-light and still heard the howl. Chalk one up to the turbo IMO. Something I think we have to realize is that a lot of these quirks that we complain about have always been there, we just couldn't hear them over the engine. Now we hear all kinds of stuff. Of course, there are some problems out there that shouldn't be taken lightly.

 

Sometimes the loud 2nd generation trucks kept us from hearing all these weird sounds I like the quiet new diesels but sometimes miss the rumble.

 

My brother has an '03. I've driven with him on loads of trips. No hummmm. He drives in mine, and it just about drives him nuts.