A shot of the upper housing on a spare Class 50 exhauster we have. The ex-class 37 exhausters obtained from C.F. Booths are basically the same as a class 50's exhauster, but are not exactly the same. The main difference is the connections on the upper housing which are in different places, to suit the location in each class of locomotive, and the method of lubrication. Fortunately the actual upper housing itself is universal and as such can easily be modified to suit both classes, and the lubrication system can be changed if you have the components. September 2009.