68RFE gear searching

[stanrat]

The set-up: 2011 2500 HO Laramie towing TT in tow/haul + Exh brake + cruise control on the flats, 49k miles on truck. Suddenly, the speed slowly drops & requires me to manually increase speed via the cruise control. I turn off CC & go manual. This slow-down, downshift to speed back up to 62MPH, continues for about 10 min then all is well with the rest of the trip home.
What's the dang deal?

 

[transe]

Bad cruise control switch? Perhaps the Set/Decel switch is being inadvertently activated (due to a switch or wiring problem). So while you aren't hitting the switch, it still "thinks" you are pushing the Decel function.

Hard to pinpoint if it's only intermittent. I think a dealer scan tool will let them watch the switch states (as seen by the PCM), so a dealer tech could see whether the PCM thinks the Set/Decel switch is being pressed. But then it would have to go bad while he is testing it.

If you have Cruise on, does it ever "set" itself (when you haven't pressed Set)? That would also indicate an intermittently closing Set switch.