Hi folks.
I had some very loud blower fan and dash vibration symptoms similar to those reported by others. I had to employ a the multi-step fix, and thought others may benefit from this info.
2018 TC XLT fan became super loud on 3 and 4 - with a thrumming vibration that shook the whole dash.
I opened the cabin air filter and found a mouse nest. (See below) Cleaned it out and replaced the filter.
Vibration continued.
Opened the cabin air filter for the second time and found more material. Cleaned it out and replaced the filter.
Vibration continued.
Opened the cabin air filter for the third time - no more material. I checked a few times for more debris - none to be found.
I suspected that the squirrel cage blower was plugged. I checked around the forum and found out how to get at the blower. Just above the cabin air filter is a plastic 'cage'. Using a small nozzle on the end of a vacuum hose, I was able to extract all of the debris from the blower. (See below)
Shown below: Air cabin filter clog, attachment for vacuum, 10% of what I pulled out of the blower, view of how to access the blower with a vacuum nozzle.
Process not shown: Removing the glove box. This can be found elsewhere on the forum.
Tools and supplies required: Cabin air filter, trim removal tools, flashlight, vacuum, small nozzle attachment (I picked mine up years ago - no name on it)
Final step in the process: Take a shower.
No more noise!
I would welcome advice on how to tackle the potential future mouse residency problem...