SD45-2's on Santa Fe without flared radiators

Aside from their road numbers, how else can you tell these sd45’s apart from their sd40-2 counterparts?

From what I taught myself - i see

  • the three radiator fans on top are further apart

  • and the hood is longer, resulting in a shorter “porch”

  • the radiator grids dont stick out as far

am i missing anything?

All but your last observation are correct. The different style radiator grille change affected both SD40-2s and SD45-2s. In the case of the Santa Fe they didn’t buy any early SD40-2s before the change was made in radiator grille design, the majority of SD45-2 were built with the early design grille. The last batch of SD45-2 (5705 - 5714) had the same style grille as Santa Fe’s SD40-2s.

Another way to identify a SD45-2 from a SD40-2, is that the radiator grilles on the 45-2 are longer than on the 40-2. This carried over into the grille redesign EMD did in the 1970s.

a major giveaway is that the body on the SD40-2 is much shorter than the frame. the porches on the front and back both jut out, giving the SD40-2 an almost tank-like look. at least to me anyway

Yeah, your best bet is to check for the porches and the length.

If It’s got porches (or a snoot) over HT-C trucks it’s a 40-2. No porches, but still long and rding HT-C then it is, or at least was a 45-2.

the HT-C trucks are easily discerned by the shock absorber on the middle wheel, and the 2 sets of 3 holes on the sides, correct?

thanks for the info on the radiator grids

yep.

Another visual cue on the HTC trucks vs. the old Flexicoil truck is on the tank side of the trucks, that is to say the end of the truck closest to the fuel tank, the sideframes wrap around. On the Flexicoil trucks, they just simply stop.

Are we all missing something? Your subject vs your post confuses me. Do you want a comparison between the SD45-2 and the SD40-2? Or between the SD45 and the SD45-2? Because the difference between a 40-2 and a 45-anything is glaringly obvious, i.e. the porches. It kinda sounds like you were inquiring about the 45 & the 45-2. They’re somewhat similar. Yes, there’s the difference between flexicoil & HT-C, as has been noted. But with the exception of the SD45X, which was sort of a proto-dash-2 with 4000 hp, I’m pretty sure none of the 45-2s had flared radiators. Full hood; HT-C; no flares. Just don’t confuse it with the SD50 or spartan-cab SD60.

It’d be hard to confuse them with 50s and 60s. because the Dynamics were moved in the 50 series.

yeah the SD60s have totally cubic long hoods. nothing sticking out. the dynimic brake is now directly behind the cab (either that or the vent right behind it. i forget. someone help me out on that one)

and as far as trucks go, usually you can go by HTC vs flexicoil for SD40/45 and their dash 2 counterparts. but take note that on Conrail power, you cannot go by truck. they had all their flexicoil trucks moved to the SD40-2s as they received them. many railroads have exceptions like this.

Look at the tall doors on each side of the engine compartment. On the 40-2 there are eight on each side to service the cylinders on the V16. On the 45-2 there are ten on each side to service the cylinders on the V20.