Vibration: muffler not a cure...

[DieselViking]

So I and a few others have been complaining about various vibrations lately. Moan/Drone, etc etc. I've mentioned the moan I hear while driving that occurs around 1500 rpm. I'm going to get the pedestal a-brace installed, hopefully that does the trick.

This concerns the vibration I get at idle. First off, of course I realize that I do own a diesel truck and that diesels vibrate plain and simple. However somehow I can't be satisfied. I've got this hum/vibration that sounds like it's coming from behind the firewall. I've checked the downpipe: tight at the v-clamp and no clearance issues. I've checked the insulation on the firewall: it all seems fastened and ok. I thought it might just be my shorty exhaust into a turnout that was letting low frequency soundwaves out, hence the vibe....so, tonight I installed a straight through muffler into my system and still have it as a side-exit like before. The muffler made the truck's exhaust a whole lot more quiet. Seriously, you can barely hear the turbo now. BUT! The stupid humming/vibe from behind the firewall is still present!? Also, my bumper cover/ rear part of my bedliner is humming. Am I insane? I'm starting to think I'm just getting annoyed at the natural sound of my powerstroke...I really need to sit in someone else's truck to compare and find out if maybe I'm just losing my mind What has me confounded is that I touch other parts of the truck and even parts on the engine and don't feel any vibes. When I touch my tailpipe it feels like it's vibrating a lot though. Normal I guess?

The only thing that helps is increasing the engine speed at idle by giving it some gas...not even much...just raising the idle from around 650 rpm normal to about 750-800. I bet I'll never locate the source of the vibration. So, my question now is, when /if I get my SCT...can the idle speed be programmed by the person writing my tunes? I'd use the high-idle mod, but that sets it around 1200 rpm, and only in park. I want to raise the idle speed under all conditions, and only to about 750-800 rpm.

Am I insane?

[Mikesf250]

I Feel your pain dude I cant get any help on this either. Does your truck consume oil without having any leaks. I am waiting till my next oil change to see how much I loose. I know it is burning some but I havent paid a whole lot of attention to how bad. I think I may have an injector o-ring leaking or bad injector and maybe causing it to vibrate or the under valve cover harness may have a bad connection because I am starting to lose some power. I think I am about to destroke mine and get a cummins put in. I just cant drive around in a Dodge but at least I can get people to work on the cummins. These Stroke mechanics around Austin Tx. cant fix a go cart.

[DieselViking]

I'm gonna try re-aligning the downpipe like the guy said to in the other post and start from there. My truck has been running fine otherwise, and it consumes no oil to my knowledge. I've got no trouble codes either. I pray it's not an injector issue like you're talking about. Good luck with yours. I hope someone chimes in about tuners writing a tune for the SCT that raises the idle a little bit. That would solve it the easy way. I'll update this post with my results.

[BOILERTURF2387]

I have the same exact vibration problem. I was going to try realigning the downpipe this weekend as well. I really do think my 4 in pipe is barely touchin my firewall somewhere. I've thought about wrapping the pipe with cloth exhaust wrap just to see what happens. Good luck and I'll keep ya posted

[Mikesf250]

I have checked for rubbing but all I have is wicked vibration from exhaust or turbo. Like i said realignment did not work with it cold so I wil try when its warmed up..

[demolitionman]

I got it too in my 06 6.0L and honestly I checked the truck out, no actual engine tranny etc issues including engine and tranny mounts (which I thought at first was the issue)...sooooo.....my quick and very easy fix for this problem...I put on Brooks and Dunn Hillbilly Deluxe in the cd player and crank it...problem solved!! And such and easy fix, on a scale of 1 to 10, I gave it a 4 and thats because you have to reach forward towards the dash and push that tiny little button to select the cd option.

[dhanna6powerstroke]

When I worked at the dealership, we welded metal hangers with rubber insulators on the intermediate pipe to absorb the vibration. Might try something like that.

[Rob]

anyway you can get a video of the noise???

[cajun1963]

Originally Posted by DieselViking

So I and a few others have been complaining about various vibrations lately. Moan/Drone, etc etc. I've mentioned the moan I hear while driving that occurs around 1500 rpm. I'm going to get the pedestal a-brace installed, hopefully that does the trick.

This concerns the vibration I get at idle. First off, of course I realize that I do own a diesel truck and that diesels vibrate plain and simple. However somehow I can't be satisfied. I've got this hum/vibration that sounds like it's coming from behind the firewall. I've checked the downpipe: tight at the v-clamp and no clearance issues. I've checked the insulation on the firewall: it all seems fastened and ok. I thought it might just be my shorty exhaust into a turnout that was letting low frequency soundwaves out, hence the vibe....so, tonight I installed a straight through muffler into my system and still have it as a side-exit like before. The muffler made the truck's exhaust a whole lot more quiet. Seriously, you can barely hear the turbo now. BUT! The stupid humming/vibe from behind the firewall is still present!? Also, my bumper cover/ rear part of my bedliner is humming. Am I insane? I'm starting to think I'm just getting annoyed at the natural sound of my powerstroke...I really need to sit in someone else's truck to compare and find out if maybe I'm just losing my mind What has me confounded is that I touch other parts of the truck and even parts on the engine and don't feel any vibes. When I touch my tailpipe it feels like it's vibrating a lot though. Normal I guess?

The only thing that helps is increasing the engine speed at idle by giving it some gas...not even much...just raising the idle from around 650 rpm normal to about 750-800. I bet I'll never locate the source of the vibration. So, my question now is, when /if I get my SCT...can the idle speed be programmed by the person writing my tunes? I'd use the high-idle mod, but that sets it around 1200 rpm, and only in park. I want to raise the idle speed under all conditions, and only to about 750-800 rpm.

Am I insane?

I have that same aggravating vibration too. It started after I had my head gaskets changed. The dealership is no help. All they can say is What vibration? Crap drives me nuts at red lights.