We had a lot of the C-628's (7100's at that time) as well as C-630's (7800's) on the San Joaquin Division in the late 1960's. While I was a brakeman, and not in engine service, I was well aware that they were not particularly reliable, possibly because they required more maintenance than the EMD's and weren't getting enough time in the shops.

I was low senority, which means I almost always rode the head-end (more work for the head brakeman compared to those guys on the caboose, especially if picking up and setting out en route) which was fine with me. More than once (or as a Cheryl Crow song says, more than twice) we pulled slowly along into Roseville or Fresno with one or more Alco shut down and one or two EMD units left to get us in. If my memory serves me right, a sharp hoghead could get an occasional stubborn GP9 to go through transition by the judicious use of some string inside the electrical cabinet at the rear of the cab. The SD40's and 45's never seemed to need any tweaking en route.