Help!!!!! bogs down

Ok guys new lightbar runs fine when bar isn’t on. I turn the bar on and run In high gear and the motor bogs down. I’m currently running a large car battery. Seems to be fine when lights off. I know ppl are relocating the voltage regulator on the 08 to the 09 location but I don’t think that’s the issue curious if a 2nd battery with light and winch run to 2nd battery could cure my issue.