GM-GMC: Transmission, transmission code, o2 sensor

Question
1997 GMC 1/2 ton. I ran a diagnostic scan with an acton super super scanner codes were Po137 o2 sensor and P1870 transmission comp slipping.       the problem with the veh. is sluggish which would agree with the diagnostic.my question is the transmission code is there something external electical to look at or is it worth changing the trany filter and fliud?

Answer
P1870 - Transmission Component Slipping

I do not know what the slipping part might be.  I doubt that it is serviceable from the exterior of the transmission.

If it has been a while since the transmission was serviced, changing the fluid and filter might help.  But, if the fluid is burned and the filter plugged, new fluid and a filter may cause "transmission shock" and cause it to stop working.