I say the trans and screw aamco those guys don't know diddly about transmissions. And as far as the freebie governor springs that's a bad idea from the get go my neighbor did that and ended up blowing his engine. Take the truck into a mom and pop trans place have them ceck it I bet its bad. Aamco says its good cus they probably botched the rebuild to begin with. Also 70 is normal to be at 2k if you've got 355s if you've got 410s and that's what you're at you've got some serious diagnosing to do