help - diagnose resonant noise when stopped at traffic light and gear engaged (1 Viewer)

[r2550g]

Hi, I have a 2007 LC with 220K miles. the truck runs fine and smooth but has had resonant noise at traffic stop when gear is engaged. The noise is quite noticeable and very annoying. The noise is gone when I shift gear to N or P positions, also the noise is NOT noticeable while car is moving. the noise seems resonant and low frequency sound (like from a boom box).

Has anyone had this issue? Your input is greatly appreciated! Thank you very much in advance!

 

[MongooseGA]

Initially I thought heat shield rattle, but you said low boom.

Is the frame weight on your truck still?

When I first bought mine, I experienced something similar. You could 'feel' it in your ears and top of your head, very low tone. Eventually it went away, possibly when I replaced something but couldn't say. Frame weight has always been on my truck, fwiw.

 

[FxFormat]

search exhaust booming at idle

 

[r2550g]

Thank you MongooseGA for the quick reply! Yes, the frame weight is. You are right, it is low tone noise and easily heard. The noise is annoying but not unbearable to me on the driver seat. But someone on passenger seat complained and said it was too loud and hurt her ears. LOL

Do you by chance remember what parts you replaced to make the noise go away?

Thanks

 

[r2550g]

search exhaust booming at idle

Thank you very much! I will do.

 

[MongooseGA]

Do you by chance remember what parts you replaced to make the noise go away?

Thanks

Nothing specifically for it. Every piece of my suspension has been replaced so I figured it was possible it insulated the frame differently

 

[hickuptruck]

Pretty common problem. Start with the frame weights, and also the exhaust muffler weight

 

[r2550g]

search exhaust booming at idle

Thanks. Read thru the thread and TSB doc, the symptoms were about the same as described in that doc, the only thing was the doc covered LC thru 2006 and mine is 2007. 2006 and 2007 is the same so I guess the doc would apply to my 2007 LC too.

 

[Mark WV]

Definitely check the weight on the back of the muffler - it may have been removed or rusted off.

 

[thebeedeegee]

Mine did this and just recently stopped. Have no idea why, but it doesn't do it anymore.

 

[Bisho]

Is your a/c on? I get a rumble at idle when stopped in gear. If I turn off the A/c it goes away. I’m hoping I have a loose bolt, I just haven’t had a chance to check it out.

 

[FxFormat]

On mine, if the AC is on, the RPM is a little higher, taking it out of that resonance zone. If you notice in the morning, you won't hear that droning when your truck is cold, only when it warms up and idle in gear it'll make that humming noise. It's more prevalent in the 06-07 than earlier years.

 

[r2550g]

On mine, if the AC is on, the RPM is a little higher, taking it out of that resonance zone. If you notice in the morning, you won't hear that droning when your truck is cold, only when it warms up and idle in gear it'll make that humming noise. It's more prevalent in the 06-07 than earlier years.

Thank you FxFormat! That's exactly the symptoms I have experienced with my truck.

 

[r2550g]

Is your a/c on? I get a rumble at idle when stopped in gear. If I turn off the A/c it goes away. I’m hoping I have a loose bolt, I just haven’t had a chance to check it out.

The booming noise seems not related to a/c. It happens when the truck is hot and idle and in gear (R or Ds), whether a/c is on or not. There is no booming noise when truck is first started.

 

[r2550g]

Pretty common problem. Start with the frame weights, and also the exhaust muffler weight

Thank you hickuptruck! I found one frame weight on the frame on driver side. I do not know how to check if it is good or not but it looks okay to me. I do not know what muffler weight looks like, I did not find anything similar near muffler. Here is a pic, not sure if that is a weight or damper.

 

[r2550g]

Thank you hickuptruck! I found one frame weight on the frame on driver side. I do not know how to check if it is good or not but it looks okay to me. I do not know what muffler weight looks like, I did not find anything similar near muffler. Here is a pic, not sure if that is a weight or damper.

View attachment 2488945

View attachment 2488946

One more puc

 

[Mark WV]

The exhaust weight is in the silver “cage” in your first pic. So that is apparently not your issue

 

[r2550g]

The exhaust weight is in the silver “cage” in your first pic. So that is apparently not your issue

Thanks for the info!

 

[atk406]

I have the same sound under the same conditions.

 

[NYLXer]

Wow, same issue. Once I hit 1,000 rpm the noise dissipates. If the idle is turned up would it solve this?