If I had only one truck with a allison I would be confused but I have a M931A1 and it has never done any of these. I have heard what many on the site saying military 10w is military spec but 10w has no adatives for auto trans use. Plus Dex3 tried and tested.Mine downshifts hard as well. I am somewhat relieved that "they all do it" after
reading this thread, well, seems like most. So perhaps a filter change is in
my future and a change to DEX 3 at the same time.
I was most concerned for use on-road in the snow, seems like it would be an
invitation to loose traction coming to a stop...
My M923A2 arrived with 10w and the shift from 1st to 2nd would jar your teeth! I changed to oil to dex3 and 70% of that stopped. I then adjusted the cable to the trans (located on the IP behind the throttle cam) and the shift points were lowered to less RPM.
I dont accept people saying its normal for a hard 1 to 2 shift or down shift. It can be corrected.