GE Question

I came across this photo ( I didn’t take it) of a Frisco U30B and on the side in large paint is says XR Series. What was the XR Series? I don’t recall seeing it before or was it a Frisco thing?

Thanks everyone!

GE used this as a means of promoting electrical improvements to their U series units in the early '70s in reply to EMD’s -2s. XR= eXtra Reliability. They could be referred to as -6s, if referenced back from GE’s next new model line, the-7s. Their predecessors likewise could have been -5s. So, an early U30B would have been a Dash5-30B, a U25C would have been a Dash5-25C.

In addition to Frisco’s U30Bs, L&N U30Cs carried the XR logo on the bottom of the cab side.

Interesting Info, thanks PBenham!