Harmonic Balancer...

From : charles hall

Q: hello all i have a 1995 dodge diesel with auto trans. here is my problem between about 65mph and 70mph where i spend most of my time the transmission will drop out of od. ie..the rpms increase. then it will go back into od. ie...rpms drop. this happens at low loads typically a level road or even a very slight downgrade. it will keep cycling every 30 seconds to a minute. this is a major pain in the ass! if i get over 70 problems goes away. if i am pulling a grade at any speed problem goes away. hope a smart dodge guy takes pity on me and tells me what the hell is going on. thanks for the help...dave could be the tps. roy hello roy im afraid i dont know what a tps is. could you give me a little more info thanks...dave .