Starter? Batt?

03 PETERBILT 379 C-15
Jump started my truck this am.
Waited a few min idled up to 750 or so not to high 65' out side.
went to store for 20 min.
come back heard loud winning on right side of truck
fogured it was the starter being stuck on but i dident hear that when i first started and ideled it when i left.
i shut it off .
waited a few seconds turned key to acc. no noise just usual bells and rings ,went and turned it over and no noise just the starter soundind like the batteries are dead .
Put a jump on it it turned over for a second thats it .
when i hook jump cables up i get no action like little sparks when hooking cables up nothing now .not on either end if calels. Info please im loaded and unlod in am and load at 1 pm for washington .lol

 

Grinding on right side was my PTO i vacumed and hit engadge to ckean under it and forgot, case solved on that deal.

Batteries are 5 mo old new
new starter .
Thing is when i start my truck i wait for whissels and bells to clear and then i have to give the peddal a quick hit to get ALT guage to work .
A nad when i do that my lights get alittle brighter ?

 

IDK

 

Staryer staying on.
my power cable was not very tight and was sparking.
coyldent see it in the day .
the night i posted i went ti start it and it sparked goid.
tightened up all nuts and bolts on stRter and no problens.
idk seened to work.