Tried it in level 1 and no surge. I live in San Diego and can go from sea level to over 4000 feet in about 30 minutes. I experience this going up the winding mountain roads in level 2. Just had my truck reflashed by the dealer for TSB for the rev up mystery shift just before installing the gryphon. Reflash had fixed the factory problem so I cannot point at factory settings, went up the same grade in stock, level 1 and level 2 and only felt the surge in 2. Will fill up with 91 octane in a couple of days and switch to level 3. I already know I want to get a 87 performance, the tow does what it is supposed to do and that is hold the gear longer but I think the performance tune may be more to my liking for every day driving. I do over 40,000 miles a year. Like this product A LOT!!!!! will give PHP a call after I have tried the 91 performance tune just so I have as much information for them as possible.
