Ford: transmission, shift linkage, torque converter

Question
I have a 1999 f250 superduty.(5.4,4R100) Ford dealer says to refill torque converter, need special pump so I should let them do it. Is this correct or can I do it by filling through fill tube and pan? Also , just purchased a 1999 F150(4.2,ER70W) with 47500 miles. Right after purchase,and about 800 miles later, the transmission locks up when it shifts into 3rd, it is like you reach down and yank up the emergency brake. Ichanged filter and fluid, looked fine, but the yellow plug was in it from the fill tube so I assume it was never changed. Any help with these is greatly appreciated.

Answer
SAM

to answer your first question yes you need a special pump.what ford doesnt tell you is you can buy one.you can try advance auto or autozone,if they dont have one try a performane auto shop.i think they go for about fifty bucks. as for the second question it sounds like either your shift linkage could be binding.check the linkage from shifter to transmission,at the trans look to see if the adjustment moved.if not there its internal,there are adjustment you can do there but unless you are mechanically inclined its hard to do.if you want to try it write back with the model of trans and ill try to talk you through it.hope this helps.

ken