2005 5.4L with 106000 miles on it that I use to plow my driveway. I was plowing last night and when I shifted quickly from reverse to drive it gave me the trans fault message and blinking O/D light. But no other issues. I’ve since turned the truck off and back on without the messsge coming back. Drove it with no issue too.

I checked it with my scanner today and the two codes it gave me were 0720 and 2106. From searching this site most people talk about the truck shifting rough, slipping trans or it being in limp mode. It doesn’t seem to be doing any of that.

Trans fluid looks good too and the trans was replaced two years ago at about 96k miles. Just not sure where to start. I have freeze frame data from when the codes were pulled and none of the data seems out of range.

just not sure where to start or if I should wait and see if the truck will display the messsge again? Maybe I just shifted too quickly from reverse to drive while accelerating?

 

Every code has pinpoint tests in the PCED
That is where you start
Especially if the trans has been rebuilt
At least read through the tests, you sure m might not be able to do them without specialized test equipment
Your county library should have AllData and that PCED in digital format, you should be able to print pages for free
That's what I do
I do not have every year of PCED, and they change things enough that you just about need the right year when dealing with pinpoint tests

 

Sounds like a one-off glitch, especially if the truck is shifting fine and fluid looks good. Codes 0720 and 2106 usually point to a pressure control solenoid / TCM issue, which can be triggered by a hard shift from R→D while moving. I’d clear the codes and keep an eye on it—if it happens again, check solenoids and wiring, but one quick shift probably caused a momentary fault.