The locomotive model designation is interpreted as follows: B (B type truck arrangement, 2 axles per truck) 40 (4000 horsepower) -8 (the generation when it was designed, in this case meaning the late 1980s) W (Widecab).
ATSF was the only railroad to order the B40-8W, and a B unit (cabless booster unit) was almost made with it, but because the price would have been the same for B40-8Ws with cabs or without, they decided to order units with cabs only.
All of ATSF's B40-8Ws became part of BNSF Railway, and many of them were repainted into BNSF's "Heritage 2" paint scheme.
In mid-2010, BNSF put 15 B40-8Ws up for sale. These units were on long-term lease and were returned to their leasor. Three units have been sold to the Providence and Worcester Railroad in Massachusetts.