British Built
Scottish Region
During the late 1980s and 1990s, Class 37/4s were the usual traction over the West Highland route, assisted by Class 37/0s on occasions. With the advent of EWS, other sub-classes found common use, including LoadHaul liveried Class 37/5 no. 37517 which was seen at Fort William SP on June 20th 1999
New Built Classifications
| 1000 Class | 90 Class | D17/1 Class | DE3 Class |
| 17/3 Class | 1851 Class |
Reclassifications
| 87 Class | Class 37 | Class 37/0 | Class 37/3 |
| Class 37/4 | Class 37/5 | Class 37/6 | Class 37/7 |
| Class 97/3 |
Re-engineered
| Class 37/9 | EWS IU |