Sad Story On a Gear Vendors OD

I tow cars and trucks half way across the state in OD, on a dolly with my 2000 Dakota.
167,000 hard tuck use miles and never a trans issue (except maybe a delayed 2-3 shift when cold for that last 20K miles) despite the 1990's-early 00's reputation for any MFG having massive trans failures.
The OD turns my 3.92 axle into a 2.7 ratio. Best of both worlds.

The trick is to keep it out of OD until you are at or near cruise speed, and if you want engine braking, turn it off before you prepare to stop.