I forgot to check last night.
I think DT may be correct. 2.5?:1 sounds about right. I know my Chevy is 2.72:1, BUT can't remember the Taco's
If you are calculating gear ratio for bigger tires you should use the highgear ratio. In the 2001 Tacoma the OD is 0.7. Then you need the diff. ratio. In my 2001 Tacoma it's 4.10:1
You don't use the T-case ratio, because it's 1:1 in this case.
03TRDBlack wrote: " What ratio do I use for that little box?"
What little box?
BTW, each gear in the transmission has a different ratio, thats why it has to shift.