[Only Toyota for me]

I take it you were going slow in 2nd, and it wouldn't drop to 1st?

If this is the case, 1st gear in these trucks is a very low gear and will only drop down if you are going slow enough.

Were you in D mode or S-6 mode? YOu know in gears 1-3 you lose WOT in S-mode even with TH engaged don't you?

I can help you better if i had a little more info. Speed, etc...