Simon3766 Report post Posted May 15, 2021 My 2000 Monaco Diplomat with Cummins 8.3 and Allison 3000 electronic shift transmission suddenly went into neutral and won't shift to any other gear. Running perfect until then. No burnt smell to fluid and fluid is full. No grind or jerk to indicate any problem. Any ideas? Share this post Link to post Share on other sites
sstgermain Report post Posted May 15, 2021 From a Google search: "The Allison shift controls have what we call "Shift inhibits", These are circumstances when the transmission ECU prevents the transmission from going into gear to prevent damage. The most common one is the engine RPM is to high and we inhibit range to prevent shock loading the transmission when it goes into gear. So your transmission is working as designed, anything over 900 RPM can cause the inhibit. The way to tell when this is happening is the keypad digit will flash." For sure too high idle and too low battery voltage will prevent proper transmission operation. Share this post Link to post Share on other sites
manholt Report post Posted May 15, 2021 Happened to me in a new WB Tour DP 2007. I parked it, turned off engine, re started and put trans in D....Last time it happened. Share this post Link to post Share on other sites
