Had the truck checked out today at the Chevy dealer. He recommended that I get rid of the three way battery cables terminal. They have been problems for 20 years or more. He stated that running the motor without a battery in the loop, will kill the engine. That's old school. I'm going to strip all the red molded rubber off the cable ends and hook it up using an adapter from AutoZone as Goostoff recommended. Idealy, I would like to hook up another battery in parallel for redundancy. I have an unused battery tray on the left side.
