I have an '02 4x4, 5.4, w/ towing package and I just discovered today that it has the 4R70W tranny. Does this sound right?

I was under the impression that trucks w/ the 4.6 normally came with this tranny, and that trucks with the 5.4 came with a stronger, rectangular shaped transmission.

Will my transmission hold up to towing, offroading, oversized tires, etc?

 

Yes, that's correct. The ONLY F-150's with the 4R100 (the better one) is the Harlely Davidson and the L. They got them for the performace benefit and strength to handle the S/C. I have had two trucks with a combined mileage of 135,000 and never a problem (knock on wood). The one thing that sucks is in a Forum like this you pretty much only hear the bad stuff, which can sometimes make it sound like there's lots of problems with something. But yes, you have the 4R70W.