Sounds Different at Idle

[X JBM X]

If you haven't read any of my other threads, I'm still fairly new to the Diesel world.

My truck makes this terrible sound at idle. If you thought a diesel driving down the road was loud, multiply it by 2, and that's where I'm at. Definitely wake the neighbors in the morning loud, but again, only at idle. I'm not sure if it's supposed to sound like this and I'm being paranoid, but the truck just sounds different. I'm not sure how to describe it. If I bring up the RPM's from ~650 where they sit at idle to about ~800, the sound goes away.

The truck runs great, drives great, has plenty of power throughout the powerband, but just sounds terrible at idle. I think of it as if I were chewing on a mouthful of rocks.

It will also make this sound when driving, and then letting off the throttle to coast.

Are my RPM's just going too low, and the truck doesn't like it? I was thinking maybe idler pully? I really haven't the foggiest idea.

It could be what this thing is supposed to sound like, and I'm just not used to it.

Thoughts or suggestions?

[capcalvin]

The 7.3s do have a lower tone than the newer ones. Some of the ones i've heard are kind of gravelly like you described. How long have you had it? Maybe you just have to get used to it? I would find someone with the same engine and pull up next to them and compare sounds.

[X JBM X]

I guess I've had it for about 3 weeks, and really only been driving it for 2.

It's definitely a lower pitched, gravelly kind of sound. and then once I get moving or get on throttle it sounds like a normal diesel (at least an older one, cuz the new ones are so damn quiet).

[02stroker250]

mine idles at about 7 or 800 rpms idk y yours would be idiling at 450 reckon it could be something to do with that

[X JBM X]

Still looking for suggestions after a few weeks...I don't think it's supposed to be this loud.

[JSchuricht]

If it's an auto, crawl underneath and check the flex plate.

[X JBM X]

Where might I find said flex plate? What's it look like and where's it located?

[JSchuricht]

The flexplate is the piece that connects the engine to the transmission, and it looks like a large metal plate. Easiest thing to do is start the truck and crawl underneath to see if you can determine where the noise is coming from. If it sounds like it's from between the motor and trans, then it may be the flexplate. The flexplate's teeth engage the starter, and there is a cover plate just in front of the trans oil pan that you can pull to get a better look.

I had mine go out a few years ago. It turned itself into a doughnut and made the truck extremely noisy at idle, sounded like something was getting chewed up. Cost about $90 from the local parts store.

[99PSD-White]

mine is starting to sound funny to. Can the flex plate expode and mess other things up? Also mine makes more of a noise when its in drive and idleing than when in park idleing

[X JBM X]

So my mechanic told me last week that it's the torque converter. I don't see how this makes much sense.

The truck is only really loud at idle, whether in gear or not, and has plenty of power.

Anybody heard of this? I'm calling bull**** on the tc, that just doesn't make sense to me.