1004ron

Are you still looking into this?

My advice would be to use a reliable scanner like Forscan as a first step in the diagnostics, and monitor the O2 and fuel trim data.

Welcome. The smell of rotten eggs comes from the CAT which only happens when un-burnt fuel get into the CAT which is a sign of an ignition or injector issue. If its been going on for a while you may need new CAT's by now but address the fuel issue first or the new CAT's will be toast in a short time. The fact that its getting in to the cabin is a secondary issue. Have you used a reliable scanner such as Forscan to check for codes?

Is this one of the models where Ford did away with the aesthetic / acoustic cover?

Is this your own vehicle and if so have you noticed any performance impact at the onset of the noise? As a test you could run it with the serpentine belt removed.

Check the reports in the below link - sounds similar to what you're experiencing and the repairs are costly out of warranty. https://www.fordforums.com/threads/2019-ford-edge-sel-trans-issues.315266/?utm_source=google&utm_medium=organic

If you asked them to "change all fluids" that would not necessarily include the transmission seeing as its not listed as due for replacement in their documentation.

@fh4ever with it still under the Ford warranty make sure the service writer checks it in with the written concern clearly spelt out on the job sheet and that way you'll have a legal record in the event there's a failure after the warranty period. Also a good idea to contact Ford Corporate and let them know that you don't believe the dealership tech has fully understood and investigated the concerns. Yes, a second dealership is a good idea. The specialist transmission shop is good, but with it being under warranty I'd pursue Ford first.

Transmission fluid change at 30~40K miles might be prudent for a vehicle that's frequently used for towing, otherwise around 50~60K miles for typical use - being a used vehicle with unknown history is may be good insurance to change it early. @fh4ever I have owned other vehicles that exhibited similar transmission behaviour you describe and it was considered normal. If still in doubt take a test drive in a similar vehicle at your local Ford Dealership, and if still in doubt after that have it checked by a transmission specialist shop. Do you still have warranty on your vehicle? - if so submit a warranty request.

I did all sorts of bench tests on the Dorman and based on those tests I assumed it must work, but after a good web search found that for reasons unknown the 3rd party evap valves don't work - installing a Motocraft confirmed the search results.

@RPGR90s I have used the Dorman evap purge valve and it did not work, or didn't work for long. I don't know what it is and why the third party valves don't work but can confirm that the Motocraft replacements do work. The current one I bought from this eBay seller and its been working for one year. Genuine Ford Vapor Canister Purge Solenoid GL3Z-9B325-B | eBay Get the free Forscan Lite to use with an OBDII adapter to read and reset codes. You'll find the PDF's in this thread showing the location of the canister - it's not easy to access.

Cant explain what you encountered but would recommend alignment soon after the new tires are installed.

I would not deviate from the oil weight listed in the owner's manual - is that what's being suggested?

The 2010 just like my 2017 the PTU takes 75W-140 I use AMSOIL SEVERE GEAR® 75W-140 100% Synthetic Gear Lube

Thanks for the comments and suggestions. The whine can be heard accelerating/decelerating with or without braking. I might hold-off buying parts until after the next service at which time I'll inspect the driveshaft, change PTU and RDU oils and check the drained oil. The tires have just under 10K miles on them - P Zeros bought and installed at Costco - I did inspect them and there's no sign of wear let alone cupping etc.