2014 JKUR - What is that Buzzing in the Dash?

[nwoods]

I am the new owner of a 2014 JK Unlimited Rubicon with only 45k miles on it. Occasionally, a few minutes after starting the Jeep, or periodically while on the trail, there is a buzzing sound emanating from the dashboard of my Jeep. It sounds like an electrical air compressor, but not quite. Its usually short, lasts 30 seconds at most, often less than that. It does not appear to be related to the HVAC system (blend doors, recirc flap, mixing valve, etc...). I don't think its related to the front or rear locker, because that is not engaged when I hear this buzzing. Or at least, not usually?

Any clues what I making this noise? Should it be making this noise?

 

[NatersXJ6]

There are 2 possibilities, one is the HVAC system, it goes into a standby / park mode and a big door moves behind the glovebox. Pull out the glovebox and you should be able to see it moving. Mine only does this when changing modes or about 30 seconds after shutting off the ignition.

The second, extremely annoying one… I haven’t fully figured out yet, but I’ve traced it to only happening when the transmission is at full 168 degree operating temp. I’m replacing the trans cooler lines and thermostat this weekend. Maybe I’ll try to get before and after recordings for you. It is super annoying and I’ve spent thousands trying to chase it down over the last 85k miles. Let me know what you find.

Jeep dealers will tell you it is normal. Sort of like a burning Ferrari on the side of the highway is still “in spec”.

 

[nwoods]

If I had to guess, and I am, the sound is left of center, and down low in the dash.

 

[NatersXJ6]

Watch your transmission temp. I would describe my sound as a humming / buzzing. It only occurs while accelerating, in drive, and transmission temps usually over 150, closer to 170. I suspect the sound I’m hearing is fluid bypassing a seal or valve. It got somewhat better when I took apart and cleaned out the transmission line thermal bypass.

Of course, I didn’t ask but assumed… you have an auto? I went so far as to change my torque converter, having thought I could correlate the sound with abnormal slippage, but still haven’t found it and eliminated it.

 

[nwoods]

Auto yes, but I can't connect the dots to tranny temp. It occurs sometimes a few minutes after cold startup.

 

[NatersXJ6]

I’ll make an attempt at recording and posting mine tomorrow. My link to trans temp is thin at best, but the list of otherwise eliminated stuff is really long. Interestingly, the noise in my Jeep is hard to hear from the passenger seat but really obvious from the drivers. It seems to come from the lower left dashboard / transmission tunnel, only happens under forward acceleration, started at about 85k miles and has gotten progressively worse over the next 75k, although still seems random. Some days there is nothing and the Jeep feels young again, other days it starts buzzing right from a cold start, but mostly when the tranny warms up.

I’ve chased a lot of stupid stuff, like putting new clips on all the insulating blanket on the firewall when they loosened…. But in the end, it remains a buzzing / whirring that I am convinced is tied to the transmission.

For anyone about to say it… not the driveshaft or front diff. I drove around for over a month with my front driveshaft and carrier on the workbench… still had the noise.

 

[Hegear]

Mine does it. I think it’s the vacuum pump. It sounds just like a small air compressor.

 

[Zeep]

Possible debris in the squirrel cage?

 

[nwoods]

Here is a short (11 second) video my wife shot that happened to capture the buzzing noise in action. Its quite noticeable when it stops. Sorry for the background noise, it was raining and kinda icy, so the sleet was pinging off the roof quite noisily.

Buzzing Noise in JK