The 4-8-4 #5113,
Before the dieselisation, the locomotives that pulled freight and passenger were steam powered. The workhorse and workhorse was the 4-8-4 Northern. After purchasing the Rock Island railroad rights, the employees rebuilt and sent the #5113 to the CI main line in Evans, Illinois. In the 1990s, the locomotive was converted into an oil burning locomotive. Afterwards, it was designate to pulling tourist trains and sometimes freight if need be.
The 4-6-0 #237,
After the purchase of the Chicago and Northwestern, The Blac Rail bought one of the #237, one of the last steam locomotive. It was rebuilt in the last 1990s and put back into operational duties in 2004 where it only pulled passenger trains along it's old rail lines. It too is an oil burning locomotive and often beats the 5113.
The Mini Bulls,
After the Central Illinois Railroad was started, it was decided that both steam locomotives would pull commuter trains on special event days including the local sports teams (excluding the Cubs). Both are currently awaiting their numbers and oil conversion.