I’m not exactly sure when the pump completely seized. I stopped for gas on the way home from the dealership and the truck wouldn’t start. After trying to jump start it, I called AAA and they towed it home. The next morning I pulled the starter out of the block with the wiring attached. The bendix worked, but motor didn’t. I decided the wrecker driver was right and bought a replacement at $ 359.00. Same result. Went online and researched what else it could be and found out about the buss on the battery being fused. Volt meter told which fuse was blown. A new buss was a dealer item, so I jumped it to ( with jumper cables)troubleshoot further. First time it started fine and ran for ten minutes at idle then died. Restarted with a eye to eye battery cable and smoke came from the front of the engine. Started troubleshooting the next morning ( thought I had burned something electrical with the jumper wire) and found nothing wrong electrical. Restarted the truck and could see (in the daylight) that the belt was slipping on the crank pulley. Found the water pump pulley too hot to touch. Pulled the belt off and found the pump seized. Engine never ran hot or leaked any water. I’m 63 years old and have never seen this type of failure before.