Installed new forward clutch disks in allison tt2122 trans but has to warm up 40 minutes before it will move any ideas?
Is the oil foaming? It's been a long time but I recall at the top of the suction tube there is a rubber seal ring that can suck air. as the oil warms it will flow more freely and start working better. The ones I worked with ran Dexron oil, but I do remember the foaming issue. I think the entire trans had to be disassembled to fix it. My experience was with A-66's so yours may be different.