If your running K+N filters ,you might try cleaning the the MAF sensor in the the air induction tube.their have been reports of the kn's being to oily and it contaminates the sensor upstream from the filter.

But get the codes when you can.
There are more things that can cause the light
DPFE sensor
egr valve
02 sensors
intake gaskets

Etc::::::
Just a few
Rich

On edit after thinking about your shifting problem ,
you may have codes that point towards your shift solenoids within the tranny.
The 4r100 use electronic shift solenoids to actually shift it .most common cause is dirty trans fluid causing sticky shift solenoids .
Post the codes to be sure .

If they say you have alot of codes ,have them clear them and drive for a few days and wait for the light to come back on and get them reread.

Rich