Oh boy things get cloudier. According to a call I just received back from a master tech at Allison main headquarters, there is no need to change the filters or Transynd on a Gen IV tranny, unless one of two conditions occur. 1) you get the wrench icon or 2) FIVE calendar years from in service. There is no mileage limitation anymore. Ultimately, he convinced me to go another year. As an aside, he was pretty proud to tell me, something that I already knew, these tranny's are near bulletproof and failures are practically unheard of. Then of course the conversation turned to fluid analysis. Bottom line in the motorhome duty cycle, his comment was something to the effect of "if you don't mind throwing money away..." These tranny's aren't even stressed in a typical motorhome duty cycle. Last thing he said to me was what other component in your motorhome has a warranty any where close to the Allison warranty? Enuff said!