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?