I was looking at the summit catalog and saw that BD has a plug in product called the "Tow-loc" and another one thats supposed to help your trans live longer.

So, does any of those things work or save my $$$ and worry about a bling trans when my stocker goes out???

Btw I have a bone stock 2001 Ford 7.3 F350 dually.....

it electronically ups the line pressure for the transmission.

most chip programmers do the exact same thing.

I'd say that you're better off spending the 100ish or so on the hardware to do it correctly.
transgo tugger HD2 kit (http://www.bulkpart.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=2&Product_Code=T36169EA&Category_Code=E4OD-4R100vbkits&Product_Count=1)

that will help prolong the transmission from stock as there is more holding power on the clutches and you can adjust how firm your shifts hit.

Be aware that the weakest link in an '01 4R100 is the torque converter. If you spend the money on a good one and the tugger kit you'll be pleased with the results and will greatly prolong the life of the transmission.