I think puretacoma.com has a front air locker.. I think the a trac system just applies brake pressure to the wheel spinning to transfer power to the other wheel. I would go with the air locker because I'm sure they're both pretty pricey
Google it. Videos with ARB air locker installed. $940-$1050 for the parts alone. Cost of a shop to install . Air compressor to actuate the locker. Total $2200-$3000