When downloading a tune to the ECM the touchscreen on the tuner states that it requires 32 minutes, but usually goes a bit faster than that. There are literally dozens of safety parameters built in to the tuner. Some of them are preset and almost all of them are adjustable to your liking. AKA, you can err on the side of safety and set your parameters lower than necessary. The only downside is the truck will de-fuel before it builds any real power. If you exceed any preset threshold, the truck will de-fuel and possibly go into limp mode to prevent any possibility of catastrophic damage to the engine or drive train. This is easily resettable and takes only seconds, as the tuner also doubles as a diagnostic tool. Tripped codes and idiot lights can be reset no problem. I've only ever had my truck go into limp mode once. I launched hard from a dead stop, and didn't lock up the TC first. It was very jerky. A little wrench showed up on the dash and the truck wouldn't go over 40. I pulled over and reset the code. Ran like a champ again. Spartan does offer a TCM upgrade for about $600, but I never bought it. Might be a good idea considering how much power these trucks are putting out. Supposed to be worth an additional 2-3 tenths improvement in the quarter mile too.
