2002 Ram 1500 with a 4 speed auto 45 RFE at 102K?

if it wasn't acting up before you installed the remote start system id disconnect it and see if it was what was making the transmission act up,its possible its wired wrong,if you wired it in to something that's affecting the compute it can make the transmission act up,if that isn't it then it may be time to visit a transmission shop for a proper diagnoses on it,good luck.