1998 chevy silverado, 350 (5.7), was going 55mph with cruise on, felt a stall, smelled something like burning rubber, the engine started idling down, engine died, and the truck would not restart. No visible problem under the hood. What do you make of this?

 

Time to start checking the basics...

Fuel pump running and putting out proper pressure
Fuel Filter not clogged
Do you have spark when turning it over
Check all fuses

Fuel pumps are common on the Vortec motors. As far as the burned rubber I am not sure what would give that smell and stop the motor from running.