tranny fluid
put in dexrom/mercon and you might as well drop off your truck at a transmission shop and tell them to rebuild it... that fluid has a friction modifier in it to help with firmer shifts, mopar transmissions however are designed to slip a little when they shift, you will want to run mopar ATF+4, its synthetic, go to a dealership, stay away from walmart, thats the rejection batch that they can sell off, but the mopar atf has a mixture that helps conserve the life of the clutch packs and the seals to allow normal function


