A Lesson in Torque, Steam vrs Diesel

mowermech wrote:
" Steam was more efficient than diesel/electric, however the steam engines were not capable of handling the grades."

Seems to me some years ago, when the diesel/electric were really taking over on the railroads, there was one grade in Colorado where they kept one steam engine (one of the HUGE ones, possibly a Malley) in service to help push the diesel/electrics over the grade. I could be wrong, it happens frequently, but I remember reading about it

Yes, very likely, but don't miss the subtle difference. Steam does not have the RPM range. Either it was geared for speed, or geared for torque. It could not do both. So while they may have used an old steam engine to help the diesel electric, that particular steam engine would be traveling slowly.