Rebuilt trans. approx. 1 year ago. We always use the sonnax tcc reg. repair valve on rebuilds.
Original Customer Complaint:
random rpm jump of 100 rpms at 60mph and up
Current Customer Complaint:
Work Completed This Visit:
When driving this truck at hghway speeds you get a fairly frequent, very quick jump in rpm. I ran a movie and the Tcc slip jumps from -3 to 31 to 95 in two frames then back to -5. Nothing on the data would call for a TCC release. The TCC apply stays on yes, the duty cycle stays at 90% and the tps only varies from 1.31 to 1.69.
Because it happens so quickly, the ecm doesn't see the slip, therefore no 1870. It seems unlikely that it is an internal prob as the TCC slip normally stays in the negative. It feels like it could be an intermittent bad wire or ground. Just putting this out to see if anyone has had something similar, save me some unnecessary headaching. Thanks for the input