No worries. This is what's nice about the forum. We all get to learn something new.
According to the famous Wikipedia...
A common product of rebuilding SD40s, and some times SD40-2s, is an SD40-3. The major addition that denotes said rebuilt unit or units as an SD40-3 is the addition of a micro-processor, and some times other modern components. The usual reasons for installing a micro-processor are improved traction control, and better fuel economy (via better injection control).
The R. J. Corman Railroad Group was using a couple of EMD SD-40T-2 ("tunnel motors") locomotives on its line in West Virginia, last time I went train chasing. I believe Corman owns 9 of 'em...
The R. J. Corman Railroad Group was using a couple of EMD SD-40T-2 ("tunnel motors") locomotives on its line in West Virginia, last time I went train chasing. I believe Corman owns 9 of 'em...
Glad you like the pic. Corman's operations on the branch here in W.Va. is rather interesting. They had been using the SD-40T-2 locos as pushers on the coal trains coming out of the Pax area, with (leased?) CSX locos (ACs) on the head-end, with a Corman hi-railer assisting along the way. There's some pics showing some of the operation on this page and even more pics on this page. That 2nd page also a pic of "a worn out CSX SD-40-2" in Hinton, WV.