Here is some basic info on trans ID that should apply to most... Don't guess yourself out of a good egg before you know for sure. Some of this can be done from inside, some of it requires crawling under. I've noticed some newer ones (Thomas, I believe) will have trans ID with other pertinent info on a decal on the interior front roof cap. I've personally seen some 3126 Cat engines with MD3060s, just not sure if an '01 would have such a trans. Those are a digital keypad, but a stick shifter does not GUARANTEE an AT545. Check first.