I have a two drive 08 F150 xlt 59000 mi and looking to trade in on a 08 lariat 4 wheel drive F150 with 104,000 mi. The truck I am looking at shutters when shifting into 3rd gear or downing into and out of passing gear. What are the most likely problems? Also the 4x4 looks like farm truck and probably pulled trailers. Should I avoid or plan on new tranny and at what cost?