The new vector field module for GPU particles requires a vector field from a 3d pacakge.
Currently there’s only support and documentation for exporting vector fields from Maya.
I am requesting support of 3ds max 
Thanks for reading.
-Mittens
This should help: https://forums.unrealengine.com/showthread.php?2274-ToolTutorial-Vector-Fields-from-splines-in-3ds-Max
I tried that, but his script doesn’t seem to install/work on my version of 3dsmax (2015)
for me it’s working on 2016 perfectly, and 2014 too