Clean all the cable connections from the battery to the engine, and all the grounds. Unbolt EVERY connection, and scrub them thoroughly with a stiff wire brush or a small wire wheel in a drill motor. Be absolutely sure there's a long cable from the battery ground post to a bolt on the bell housing, not the Mickey Mouse short braided ground cables the truck was manufactured with. That system had only one purpose- - - -cutting production costs.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!