Mechanically, the locomotive's front traction motor blower was shifted to a position above the main generator, while new thermostat valves were fitted in an attempt to prevent the overheating problems that had plagued the locomotives under load. The original Westinghouse A7EL brake system was replaced by the more modern 26L system, actuated by a new push-button console in the cab. The traction motors were also upgraded, while welding repairs were conducted on the 6SKRT engine blocks. Several blocks were later sent to the United States for repairs using the Metalock treatment; this was later deemed to be a failure as the blocks again cracked and the Metalock treatment was seen as a waste of money.