I have a 1996 Ram 2500 full size conversion van with a 318 engine.When the van reaches it operating temperature and has been driven for a hour or so like on a long trip.When you slow down to a speed of 40 to 45 mph it has a missing problem just between the speeds of 40 to 45 mph.It runs just fine at any other speeds.I have put a new speed sensor on the transmission and that has not helped the problem.Please help with any suggestions. :help: