i am having some shifting issues with my 2004r. it will shift just fine from 1-2. from 2nd to 3rd i need to let off the gas for it to change. once in 3rd it holds fine and will continue to accelerating. reverse also works fine. The change literally happened over night. drive fine one day next day like crap as soon as i got in the car. has fresh fluid, proper level. seen evrything from a stuck tv plunger to broken springs or possibly need total overhaul. what can i look for and where without tearing it out of the car first .