Put this up in the regular ECM area and should be here.

New 4L70E in a 03 Silverado that was a 5 spd.

Trans shifts fine and TCC applies above 40 > 45mph.

However as soon as I go over 70 MPH, the TCC starts oscillating On / Off every .5 or 1 second.

I can lock the TCC on with HP tuners scanner and it stays on. Everything in the scanner looks good going down the highway.

Anyone have any Ideas ?

I have Misfire disabled. With it on, the TCC would not come on due to the small cam.