my father owns a 07 with a 5.9 he recently had the transmission rebuilt. now when he goes down hill with the cruse control on it surges like it kicks in and out of cruse.
this week when he approaches a stop sign it acts like the transmission kicks into neutrol after it gets to 45 miles per hour the tach shows the rpms go to idle at 45 mph any ideas?

 

The name of this sub-forum is a little confusing, your question belongs in 3rd gen Engine and Drivetrain 2003-2007. These folks with autos all have the mighty 68RFE.