I recently have had many problems with this vehicle, from the tire rods coming out to, break line problems but now I have come across a problem that has me confused. For the past month the van has been jerking forward while driving over 35 mph... Now this problem appears to be a random occurrence but when it starts it doesn't want to stop. Somtimes I can shift to a overdrive, and it will help somewhat or so it seems but this is not always effective. Before it was doing this it would occationaly lose rpms while idling at stop lights and so on and nearly die. Now I'm not sure if this is related but if so what is the mostly likely cause of my dilemma?