Bully dog chips aren't that good. Most on here try to stay away from the bullydog, banks, etc. stuff and go with a custom tuned chip from TW, PHP, Gearhead, or DP Tuner.

If you want your trans to last definately get a bigger cooler, gauges to keep track of temps, and upgrade to a better torque converter when you rebuild it. The E4OD has trouble with the stock power of these trucks so upgrades will kill it even faster.

 

Bully Dog, Banks, Superchips, Edge, Hypertech, etc. Stay away from them. Get a chip from a good custom tuner. To list a few custom tuners- Total Diesel Performance(Tony Wildman), Power Hungry Performance(Bill), Gearhead Automotive(Matt), DP-Tuner(Jody), etc. There are quite a few more places that do custom tuning for the 7.3, but those are all good places to look.

Follow Evans above advice, get a better transmission cooler, guages, and either a PI torque convertor or one from RacerX when you rebuild the transmission. Wouldn't hurt to get a BTS or RacerX valvebody either while the transmission is out being rebuilt.