2018 Yukon XL - Mystery Rattle

[BushmanTahou]

Hey All,

 

Recently got myself a 2018 Yukon XL with the 5.3 (actually a company vehicle, but I use it as my daily driver as well.) Everything has been fantastic so far, with the exception that over the last 8000 miles since I got it I've noticed a rattle that sounds as if it's coming from deep in the dash.  It only appears at around 1200-1300 RPM under a light load, exactly the kind you get when cruising around at 45-55.  I've done all the usual stuff, trying to empty the glove box, move seats, press on different ares of the dash, all to no avail - it sounds like the noise is coming from behind the glovebox or in that area deep in the passenger side dash. I've heard that this could be an issue with the transmission fluid dipstick, but the dealer hadn't heard of any such issue and my jurry-rig of trying to secure it with zip ties didn't do anything to help. Know this is all pretty vague, but wanted to see if anyone else had run into a similar problem.

[AirForceAngler]

Could it be that your cabin filter has come loose or something is trapped near that?  The filter is located behind the glove box.  You have remove the glove box insert to access it but it's only a few screws and described in the owners manual.  Good luck!  Rattles drive me crazy!