2007 V8 Lights on After Fluid Change

Recently I bought a 2007 with 170,000 miles on it. I replaced a leaky high pressure PS line. I then did the oil, coolant, front and rear diffs, and transfer case.

I used Toyota super long life coolant and house brand synthetic 75w90 on both diffs and the T case. 2 days later the Engine light and traction control lights came on along with flashing VSC off and 4LO lights. This happened while I was driving. Could it be the fluid used for the diff?

Before the lights came on, the truck started shifting weird when picking up speed at around 45 MPH. I didn’t think too much of it then about 20 miles down the road the lights came on.

I was driving in some knee high brush and on a grid road at the time of the occurrence. So maybe I bumped something underneath? I checked and there is nothing obvious.

i pulled out my $30 scan tool and pulled the code P0976. I have searched for answers before making this post and found only similar posts with no luck to my case.

I tried disconnecting the battery for 15 minutes twice. As soon as I in leave the house the lights come on. It feels like the truck is starting off in second gear.

thanks all