Ok Ranger folks---Here is the problem. My Ranger gives a code of PO1336 only when at a high rate of speed----65-75 Mph. I have changed both sensors--the truck does not shimming or shutter at 75 Mph. My next thing to do is to change out the PCM or harmonic balancer---any suggestions--I've spent several hundred dollars already. Even took it to the dealership and they gave me the runaround. One "expert" mechanic said not to worry about it. I reset the code and it doesn't reappear until I do a high rate of speed