The issue is they were made for high speed service with high horsepower per ton ratios that meant you had enough units for the necessary traction; railroads attempting to use them in "drag" service on underpowered freights quickly experienced the "slippery" that comes with 1,000hp per axle when the "power desk" treats everything like 4,000hp = 4,000hp without regard to tractive effort.
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| Posted by Triplex on August 11, 2023 | |
I've never understood why railroads stopped buying locomotives like this, and the general shift to lower HP/TE ratios in the 1990s. If high-HP/TE locomotives were desirable for certain railroads and services before, and they clearly were, what changed?
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| Posted by xBNSFer on August 18, 2023 | |
Well, for 4-axle units, the death knell arrived with the North American Safety Cab. When applied to 4-axle units, this required a smaller fuel tank because the heavy new cabs added enough weight so that a 4-axle unit would exceed allowable axle loading limitations with bigger fuel tanks. 6-axle safety cab units could carry more fuel (two more axles to spread the load, so no issues with full size fuel tanks), and that meant less refueling stops.
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| Posted by Triplex on August 19, 2023 | |
I've heard that before, but... CN got GP40-2(W)s in the 1970s, and most were light-frame versions for extra fuel capacity. This gives me the impression that the standard frames of most US diesels are heavier than they strictly need to be.
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