I have a 94 montero 3l auto & wont shift to higher gears when on "d" stays on 1st, but will shift when done manually from 1st , 2nd & 3rd. I don't want to bring it right away to tranny shop if i could do something. There's no check engine on the dash. I've drain the tranny & used mitsu fluids. Any assistance is very much appreciated. I've got 160k on the truck