2000GT4.6

I feel ya man. I cannot get fourth after the trans warms up. Im hoping a swap to synthetic is gonna help matters out, as it shifts perfect until it gets hot.

This is my 2nd trans also. I am thinking hard about a TKO type setup. Screw the 3650, I want to put something in there that is built to beat on. Its not worth a few less hundered bucks to have to worry about it, or take them headers off yet again [:'(]

Pacman

Sounds like the problem i had with my f150. I lost 3rd,4th and 5th. i dropped my tranny, pulled the top cover off and one of the shift forks was grinded down to nothing. Im not to sure on your tranny but it could be the same thing. cheaper than having to rebuild the tranny.

Changing your fluid doesnt usually fix a problem it usually prevents a problem but it may be worth trying. If you change your fluid remember to check your old fluid with a magnet to see if there is filings in there. that will tell you if something is wearing out.

USAMuscle

The problem with disassembling a T45 is that it doesn't have a top plate, so you can't just open it up and look inside to see what's wrong like a T5. You have to pull the cluster gear and main shaft out from the back.

2000GT4.6

Yeah and there is some sort of stupid *** pin in the tailhousing thats in a hole that only has one side. There isnt any way to drive the pin out of the hole, you must need some sort of special tool to get it done.

Tried to pull the tail off mine for about 30 minutes before I said screw it.