Frame mounted trans cooler only?

[gopokes]

Just like the title, is it ok to run a frame mounted trans cooler without running lines to the radiator? I know I have seen some build threads that people have done it, but I'm having a hard time finding much in my search efforts. I won't ever be pulling anything with my truck if that matters. Oh and the tranny is a 460le behind a 5.3 engine. Any help with this would be awesome!