I've got a 2019 Atlas and have a grinding issue as well (existed the day I got it, of course didn't figure it out until after I drove off the lot). The noise sounds are identical to the noise in the video posted on this thread earlier (12-30-2018, 07:45 AM). Frequently occurs when going up hills under 30mph under slight acceleration. I've actually recreated my grinding sound without the vehicle moving. I put one foot on the brake, put the car in drive, and slightly press down on the accelerator - this causes the grinding to occur, but only at the sweet spot of just a little bit more than barely pressing the accelerator. What's bizarre is that while doing that (and while the grinding sound is occurring), if I move the shifter to the right (put in manual shift mode) then the sound goes away - if I put the shifter back to the left (automatic shift mode), the sound returns. I can go back and forth with the shifter and the grinding sounds comes and goes consistently. I've tested and confirmed this occurs in Economy, Normal and Sport modes. I know there's been talk about this occurring when the car is in a specific gear, but for the grinding issue I have, I believe I have eliminated a specific gear(s) as the cause of the problem. Also believe this eliminates my initial theory that the transmission was just at the point of a downshift when the grinding sound occurred. Anyone have any thoughts on this?
I'd appreciate it if anyone who has the grinding sound can confirm if they can also recreate it following the steps I've outlined. I've got an appt setup in a few weeks at the dealership...I'd like to go there armed with a bit more info on what others are experienced.