Ms Williams said “So many of us here at Northern were inspired by Rob’s indomitable spirit and his commitment to helping others suffering with this cruel disease.
“That’s why we want to pay tribute to this great man, help raise awareness of MND and funding which can be used to help find a cure.”
The operator said it was now working with the former Rhinos star’s family and the MND Association to create artwork for the train’s livery.
A spokesperson said the train would be unveiled at a station in West Yorkshire during an event later this year.
Jo Coker, the MND Association’s director of income generation, said: “Rob was an inspiration both on and off the pitch.
“A man who showed real courage in sharing his diagnosis and opening up a conversation about motor neurone disease which continues to this day.
“As one of the region’s most famous sons, naming a new train after him is a fantastic way to honour Rob’s life and legacy.”