Chevy and GMC Duramax Diesel Forum banner

1 - 4 of 4 Posts

·
Registered
2017 Chevrolet Silverado 3500HD LTZ
Joined
·
1 Posts
Discussion Starter #1
Hello everyone, I am hoping someone may have some insight into an issue I am having. I have tried searching (here, Google, YouTube, etc...), but have not found anything that solves my issue. I have a buzz/rattle that seems to start once the truck warms up. It happens right around the 1200 RPM range and will stop if I raise the RPMs a bit, but returns when they lower. I sounds like it is coming from the firewall area and is pretty loud. I have pulled all the dash panels, glove box, radio (to include the modules behind the screen), and center console then drove the truck. It still made the noise. I wrapped the components under the top dash panel to ensure they are not rattling, did not help. The truck doesn't vibrate, although I "think" I can feel the rattle in the gas pedal. I have climbed under the truck and do not see/feel anything loose. I am completely at a lost, minus pulling the entire dash and interior out. Has anyone experienced this before? Any help would be greatly appreciated and help lower my frustration level.

Thanks,
Phil
 

·
Registered
2007 GMC Sierra LBZ
Joined
·
108 Posts
Check the heater core lines going through firewall to make sure they are not rubbing together. That was a problem in some previous gen trucks but never heard of it for the L5P. Just a thought though. Also could make sure all bolts/nuts are tight for pass side battery tray. FYI there are three nuts fastened to firewall behind coolant reservoir that holds tray. Also make sure intercooler pipe or something is not hitting the brake master cylinder or booster. Just some thoughts.
 

·
Premium Member
Joined
·
2,874 Posts
Here is what I found in my truck, don't know if it will help with yours.

 

·
Registered
2007 GMC Sierra LBZ
Joined
·
108 Posts
That’s a good point but the ‘15 style change they put foam in there from factory so doubt that’s the issue.
 
1 - 4 of 4 Posts
Top