Bummer to hear about this ongoing gremlin of an issue.
If you've had the torque converter required replacement then the transmission required a rebuild. When the torque converter fails it causes debris throughout the transmission.
Aside from the above. If the ABS light is triggered and you're hearing ABS like noise, I'd speculate a possible hub assembly issue or corresponding sensor. Wouldn't hurt disconnect and re-connect each abs sensor and then take an allen key and remove each sensor from the hubs 1 at a time and rotate the hub by hand and use a flashlight to see if there's some grime spinning around inside the abs encoder.
Additionally if you take it in for diagnostics, I'd bring it to a dedicated transmission shop and explain problem and see if you can be present when they test drive to further explain (first-hand). They can scan tool the ABS system while rotating each wheel, drive-train and get a history of transmission codes for clues.
Thanks for the input! The noise initially sounded like an ABS when you hit brakes hard. No codes for this or for transmission. Only code/codes I have gotten lately is P0308. First time the plugs and wires were replaced and all was well. No noise for a few hundred miles. Latest code is also P0308. Initial code when noise began (can't recall; papers in vehicle and vehicle in shop) which was a couple hundred miles after second torque converter was replaced was for eoither low battery; re-program ECM and/or replace ECM. (No transmission rebuild, of course) Vehicle went into reduced power mode at that time. I was driving semi-aggresive on curvy mountain roads when it acted like it bounced into neutral. No power until it went into reduced power mode. Flooring it I could maybe get to 50-55 MPH. I was 7 miles away from nowhere when this happened...no cell service, nowhere to pull over... Once I stopped (after travelin along in low power mode) and let it sit for 10-15 minutes it went back to normal power; engine light still on. After driving for 3-4 miles I stopped briefly for 5-10 minutes. Started up and engine light was off but took to dealer and they reprogrammed ECM. Ran OK for another 2-300 miles and then the noise began. And that's where we are now. I think something broke. It comes and goes but sometimes when it comes it gets more frequent. Sometimes right out of garage and other times it takes about 100 milers of constant driving before it begins. Other times I can drive 300+ miles with no issues. Makes absolutely no sense and I know it is difficult to diagnose. I have videos out the ying-yang of the noise....
As of today, Dealer is trying to get GM Regional in Atlanta involved but from my past experience 30 years ago on an S-10 Blazer engine issue I don't have much confidence in them helping. I do have to say that the dealer has been good to me; but.............they don't know what to do. I've thought about taking it to a local transmission shop but don't really want to do that yet...although......
I don't think there's an ABS issue but I am still on original pads. Rear pads and rotors look OK and front rotors OK. Front pads are down 75%. (estimated) I plan to upgrade front pads and rotors to something similar to Power Stop Evolution pads, calipers and larger rotors. Need to get this initial issue resolved before I do anything else. Really don't want to get rid of it since I am now semi-retired and don't have the income I used to. Sometimes I think I should have bought the Durango RT or SRT; or, the Explorer Platinum....but we are where we are!
