Check Trans w/code P1870

Has anyone had the Check eng + Check Trans lite with the code being P1870?
I had this happen on normal highway driving (after a previous day of off roading/wash board roads).
Check lite cleared and it came back on after 30 min of highway driving the next day but reset it self later on in the dayand has not come on since (1400 mile trip home).
Any thoughts?

I'm getting same thing, but P1860. Its come back every day or so, won't stay away. I'm going to try contact cleaner and new grease in all the tod connectors.

John C.

P1870 means transmission components slipping.