i really don't know what trans and x-case is in it, but i know the engine is the 3.2liter 4 cylinder and it has d44 axles front and back. i don't know what gear ratio is in it either. i going to try not to tamper with too much stuff in it, i'm gonna try to leave the stock engine in it. my buddy went from 31" tires to the 35" tires you see on it now, but its never been driven with the new tires. i have the battery charging right now so tomorrow i'll see how she does with the current gear ratios, i'm hoping they don't need changing. the truck seems pretty light overall, so we'll see.