Complete Electric failure-short?Need ideas -1997 chevy truck

The truck is a 1997 chevy silverado 3/4 ton. Newer battery.
Pulled away from curb a few nights ago and it died electrically-so power-no lights -no engine-zip-Jumped it -ran fine another 10 feet then completly dead electrically. Battery shows 13 volts-jumped it again and parked it -whent it died I could here a faint electrical noise but no lights or power of any short.
Next day towed to dealer who cannot reproduce the failure after starting it many times and a test drive.
I’m thinking new battery cables and cleaning the grounds-any other ideas-
I have zero faith in this thing now and I need to hual 10 tons in two weeks with it.
It was a complete electrical shut down twice in a row- Never made it 30 feet. If it was alternator the battery would have kept the cap light going-battery is fine -6 month old interstate.
I need ideas for them to tarck down.

Could be the ignition switch, check edmunds for recalls.Try changing steering wheel tilt just for kicks, and using only 1 key in the ignition.

The first thing I would check is the positive battery cable.

Your vehicle has the side mount battery cables. And what can happen is corrosion can form under the cover for the connection at the positive terminal of the battery.

This corrosion can make a poor connection at the battery, or leech down where the terminal is crimped onto the cable making a poor connection.