Your grandfather may have been in Company B, 9th Armored Infantry Battalion, which was attached to the 6th Armored Division. They landed in England in February 1944 and on Utah Beach on July 18, 1944. On the website for the 6th Armored Division is an excerpt from a book by Milton Moncrief who was member of Company B, 9th Armored Infantry Battalion. If this is indeed your grandfathers outfit, the book will give you a very good insight of what your grandfather went through. Good Luck.