I still have a greyed out fallout jumpsuit but that doesn't seem to be related to the problem as unlikely as that sounds for the moment.
Chucksteel created a fix and attributes the problem to speedtree crashing when entering Tranquility Lane and Oasis it was caused by the speedtree effects that make the leaves move. FIXED - As noted by RoyBatty below this is a known error related to AMD card but in my case is present with an NVIDIA card.
