No Trans

[PAredneck]

Ok I guess things were going too good for too long. I finially got my rebate check from Ford for the recalled CPS I replaced 2 years ago. The day after I cash it my trans goes out. I think they put some kind of powder on the check that reacted with the shift lever when I touched it! (by, the way, I see dead people) Have a 2002 F350 4x4 108K auto trans. I noticed a low whistle this morning while running empty and thought it was just the ice on my ladder rack. Later that morning I was backing my trailer (7K) up a hill and stoped mid-way to check my mirrors. Started to back up againg and the truck shut off. I put it in N and started the truck and coasted back down the to make another run at it on a better line and nothing. P is the only position that worked. No movement in 4 wheel either. Took notice to a low whine while truck was ideling after that. Fluid top off and looks to be ok as well as the temp. Ford mechanic thought filter dropped (known problem in that trans) or valve went. Reccomends new trans because of warrenty. Dealer wants $3900. Any other time I'd grit my teeth and get it done but work is slow and I'm pinching pennies..............any thoughts? I'm thinking TC with the engine stall and from what I've been reading here. Any info or sympathy would be welcomed!
Thanks