Not fully knowledgeable on Trac Control, but what I read in other board forums, it applies the brakes first to slow the overly spinning wheel, and if that doesn't work fast enough, then it pulls the timing. I can speak from experience, that seems to be the way it works. Dayum thing pulled my timing in the middle of a slippery turn with a big a$$ 4X4 truck heading right for my window whilst I was trying to power out of the slide and out of the way of the truck. Scared the $hit out of me when it died in the middle of the intersection.......