2015 EVO Fuel water Separator going empty after turning corner

Twice after I had exited the freeway with loaded trailer's and first time 1/4 tank and 2nd time 1/2 tank of fuel. I had completed my right hand turn and the truck had just shut off with fuel in the tanks, I had check the Fuel/Water Sep and it was empty both times. Frighterliner is unable to duplicate the problem so my truck is just sitting idle in there shop Costing me $$$$$. Have anyone else had this problem?
Dealer said tanks are at 40% and working fine and unsure what is going on.

Thanks in advance

 

Thanks 6th Wheeler, I'm going to ask to speak to Forman to see what they have done so far