Allison 3060

I always check my tranny fluid level with the shift pad on every stop when we are on the road. After my factory service at Freightliner last fall, my first check showed I was 2 quarts low. Checked dipstick and it showed that all was OK. I am getting ready to head north in about a month and want to resolve this before I head out. Freightliner had no explanation as to the cause. Maybe unhook batts for a while to reset the tranny? Any other ideas?

Before this the shift pad and dipstick always matched.

Thanks
DICK