I have a 2000 ram 1500 4x4 and about three months ago it started hesitating while trying to shift into second gear, but now this only happens when I'm going slow or take it easy from a stop. When I jump on it from a stop it shifts fine. I took it to a dealership and they said all it was, was it needed a fluid change and new filter and it was done and it is still acting up. Could this problem be a sensor, vaccum module, solinoid????????

 

Could be the torque converter acting up. How many miles are on the truck and what transmission is it?