killed new Jeep Wrangler by Flat-Towing It in 4-Low !

Yes the transmission output shaft will spin due to fluid dynamics. Similar to how a torque converter works. With it in gear the shaft won't spin. These transmission do not lubricate themselves like some other manual transmissions do when they are flat towed. So if the trans was allowed to free wheel it could potentially damage the internals. Although in this case, the trans was being lubricated until it surpassed its rpm rating. LOL

You see all sorts of stuff working at a dealer. Right now I have a Ram 3500 dually with 9500 miles that the owner destroyed the rear axle on. It's a hotshot tuck, They hit something 5k miles ago (that's 5k miles in 2 weeks time) and replaced the 2 right side dually tires with Firestones and left the factory Nexens on the other side. Well they got an ABS light, I removed the sensor in the rear axle and found metal attached to it. Pullled the cover and found metal everywhere. The spider gears destroyed themselves. The reason.......the Firestones are a 1/2" larger in diameter than the OE tires. Causing the spider gears to be in continuos rotation (they are only designed to be rotating when turning corners), not in continuous operation for 5k miles! So it need a complete axle assembly. Right fender is damaged and the liner is missing, but the owner insists they didn't hit anything! LOL