I've noticed one of the locomotives I operate on the Oakville Sub is labeled G420-B under the unit number on the cab sides where the locomotive model would normally be found. What is this? The internet hasn't been helpful in trying to research the designation.
It's CNs version of classifying their locomotives: -G means General Motors (or EMD) -R meaning Road Switcher -4 as in 4 axles -20 is horsepower -and b is the second batch of units when delivered. This site will give you what the other letters mean: http://www.cnrha.ca/node/285