allison fault code?

[hapaschold]

yesterday, after parking , left running for a few minutes , put back in drive, no forward movement, looked down to be sure in drive, it was, and D light was flashing, put back in park, tried again, no forward movement, back in park again, restarted engine , all ok.
any thoughts ???

thanks

[mark45678]

what you have discribed sounds like the converter draining down? but this most of the time will happen after sitting many days with out being used! Have you changed the spin on filter yet? Allison wants us to do it at 5k then every 25k!OR it could be the NSBU switch.... next time if it does it leave it in REV or drive and see what happends? dont panic its happend to mine to! juice and 30+K later and still going strong!!! ;)

[Dmax Cutter]

I have experienced the flashing "D" as well but it was when I placed the selector from "N" to "D" while the truck was moving down my driveway. It is my thought that there was a mode that senses the movement and will not allow the transmission to engage. It happened twice before I dummied up and I had to shut down, then restart each time.