Electrical Problem

Chevy S10
4X4
4.3 L
6 cylinder
1996
40K miles

Started my truck last night easily enough, however, noted that the interior lights were flickering mildly, along with clock and headlights. Started to drive it out of the heated garage and noted it was riding a bit rough and lights continued to flicker. Shut off engine, attempted a restart, it rolled easily over for a few moments and finally turned over but then promptly died.

Waited a few moments and tried again, same rolling but turned over and stayed running. Used the moment to pull back into the garage and then killed the engine and popped the hood. Checked the battery, which I replaced not more than two months ago, along with a connector bolt (positive side), everything was tight.

Made another go to see if it could start off and it finally made a very bad grinding sound and all the lights died, everything, and a few seconds later they all came back on again.

The lights didn’t give me a steady dimming so I am hazarding that it isn’t the alternator but perhaps a Voltage Regulator, interrupting the current from the battery. Also prior to this episode the truck wasn’t riding roughly but smoothly, so I don’t think it is the spark plugs. Does anyone have any thoughts on this?

Any suggestions would be appreciated.

Take the battery cables off and clean them

I have done that already. No change.

Try a new battery