1st Generation SD-series official thread (all variations)

[SSW9389]

The SDL39s were about 10 feet shorther than an SD38/SD40. The frame was possibly used previously in EMD export locomotives. The units did use a lightweight version of the Flexicoil truck.

If those were those old Milwaukee junkers we had on the Soo Line, I believe they were sitting on SD-38/40 frames. Really lightweight engines, not unlike the branchline SD-18's we had there, as well. Regards

[MEC407]

This is what Field Guide To Modern Diesel Locomotives by Greg McDonnell has to say in regards to the SDL39:

Commissioned by the Milwaukee Road as a replacement for Alco RSC2s assigned to lines with restrictive axle-loading limits, the SDL39 was built on a short, 55-foot, 2-inch frame, powered by a turbocharged 12-645 engine and rode on customized export trucks. The 2300-h.p. C-C tipped the scales at just 250,000 pounds and managed a light-footed axle-loading of just 20.8 tons per axle.

The SD38-2 and SD40-2 are 68'10" in length, compared to the SDL39's 55'2". The SDL39 is actually a foot shorter than the little BL20-2, and they are the same weight.

Just as a random daydream/what-if scenario: if MILW had gone to GE instead of EMD, perhaps they would have ended up with a "U23CL" or something like that -- basically a U23C on a U23B frame, with a tiny fuel tank and custom trucks. Would've been interesting.

[GOLDEN-ARM]

Thanks for that correct info!!! What other loco DID share that same frame then, anyone........... ?

[USRailFan]

Thanks for that correct info!!! What other loco DID share that same frame then, anyone........... ?

GP38?

[MEC407]

The GP38/38-2, GP39/39-2, GP40/40-2, GP50, GP59, and GP60 all used a frame that was 59'2" in length.

The frames of the GP9 through GP35 (GP15-1 and GP15T excluded) were all 56'2". (The BL20-2 reused a GP9 frame.)

As far as I can tell, the SDL39 frame was completely unique in North America. EMD may have used it elsewhere in the world, but it would appear that it was not used on any other domestic models.

[USRailFan]

The GP38/38-2, GP39/39-2, GP40/40-2, GP50, GP59, and GP60 all used a frame that was 59'2" in length.

Really? I thought the GP38/38-2 and GP39/39-2 were shorter than the other 645/710-engined geeps (except the GP15-1 of course)?

[trainiax]

The GP38/38-2, GP39/39-2, GP40/40-2, GP50, GP59, and GP60 all used a frame that was 59'2" in length.

Really? I thought the GP38/38-2 and GP39/39-2 were shorter than the other 645/710-engined geeps (except the GP15-1 of course)?

The GP28, GP30 and GP35 are 56' 2" with 32' truck centers.
The GP38, GP39, GP40 (including Dash-2 variations) GP49 and GP50 are 59' 2" with 34' truck centers. The only cosmetic differences between the GP38 and GP40 series are with the radiators/fans, exhaust stacks and dynamic brakes.
The GP59 and GP60 are 59' 9" with 35' truck centers (this distinction is not often mentioned).
The SDL39 is 55' 2" with 30' truck centers and does not share its frame with any other EMD units, to my knowledge.

[Phil Hom]

Another photo showed up on page 94 of the fall 2006 issue "Classic Trains". It's more of a front end wedge shot.

[MEC407]

The test compared NREC's new N-ViroMotive 2GS-14B GenSet locomotive to a conventional six-axle SD18 locomotive pulling a 126 unit double-stack container train (6,215 tons, 7,713 ft. long) 1.8 miles from the Terminal Island dock through a series of 8 degree curves and switches up a final ascending grade of 1.08% for 2700 feet over Badger bridge down to the Long Beach switch.

Dave Davies, an NREC executive account manager at the test, said, "The final comments from Pacific Harbor Lines (PHL) engineers & personnel present were that the NREC GenSet locomotive exceeded expectations and virtually matched the heavier conventional locomotive for this test. Most impressive were the comments about how well the NREC locomotive held the rail and did not encounter wheel slip." Davies also indicated that no sand was applied to the rail during the test.

Read the full press release at:

http://tinyurl.com/jsucz

[U-Haul]

I am guessing this switcher looks similar to UPY 2O05.
http://www.rrpicturearchives.net/showPi ... ?id=212129
http://www.railpictures.net/showphotos. ... UPY%202005
Wow, a smaller, lighter, and less horsepower locomotive outdid a bigger older version. I always believed that 3 axles a truck are better than 4. That is why the GP50s, GP60s, and GP60Ms are longer assigned to money making intermodels (sic) I wonder if a 6 axle version of this Genset could be built and out preform its 4 axle brother? Here is a look at a MP15DC which the Genset is built on and a SD18.
http://trainiax.net/drawings/emd/emdmp15dc.gif'
http://trainiax.net/drawings/cd/cd-cmemdsd18dbln.gif
I am guessing the newer diesel uses less fuel which is good.

[Jtgshu]

I know that in many cases, older power is what is used around these types of terminals, (as is the case with this example, on the Pacific Harbor Lines) and a 126 car train, at 6000 plus tons is nothing to sneeze about, but to compare todays newest technology (theoretically) to a nearly 50 year old locomotive seems to be stacking their cards in their favor just a little bit.

Its an impressive feat, what the GenSet loco did never the less, but how about comparing it to something a little newer? Maybe a GP38, or better yet, an SD38, or something like that.

It just seems to me that the comparison is something a drag race between a 1962 Corvette compared to the 2006 Z06 Corvette!!!!

[MEC407]

I think the whole point is that they're trying to give the railroads a compelling reason to buy something much newer. Previously, the railroads had no reason to do so. But NRE is saying, look, this is a new locomotive and yes it's going to cost a lot of money, but you're going to save a TON of money on fuel, and you'll be cleaning up the environment too.

The reason why almost nobody bought the GP15D and GP20D from EMD was because there just weren't enough compelling reasons to do it. The GP20D was basically equal to a GP38-2 in terms of performance, and that's about it. No other major advantages, other than being equal. So why would the railroads spend $1 million on what was basically an end-cab GP38-2, when they can simply keep rebuilding their own GP38-2s and get the same result for less money?

NRE is saying that this switcher is not only equal to or better than what the railroads already have, it'll also save them money in the long run, be more reliable, be easier to service, pollute less, etc. In that light, it's a fair comparison.

[GOLDEN-ARM]

Not to bust anyones chops, especially when they tried so hard, building that "GenSet" loco, but my Jeep Wrangler, will outpull an SD-18. (4WD, low range, in first gear) What the hell kind of test, is that? Maybe for their next test, they can conclusively say, an SD-90 will outpull, and outperform, a GE 70 tonner!!! Wonder why they didn't compare it to an SD-40-2, the most common "second generation" loco, in the fleets.......

[pablo]

That's some Jeep, Golden-Arm! Must have a big block!

I think my '67 Impala might be able to out pull it too, but I could fog for mosquitoes with what comes out of the exhaust.

So...what's the market here? Let's compare...anyone know what one of these new ones might go for? And anyone know the approximate cost to rebuild a GP-38?

Dave Becker

[MEC407]

Wonder why they didn't compare it to an SD-40-2, the most common "second generation" loco, in the fleets.......

Because, as you said, that's like comparing an SD90 to a 70-tonner. It would be a pointless comparison.

Comparing the GS14B to the SD18 was a fair comparison. They have roughly the same horsepower per axle (300 for the SD18, 350 for the GS14B). The SD18 has the advantage of heavier weight and more drivers, and yet the GS14B held the rail just as well or better. That's pretty impressive!

"But wait! The GS14B has computers and the SD18 doesn't! That's not a fair comparison!"

That's the whole point. NRE needed to give the railroads a tangible reason why they should upgrade to something new.

Yeah, you could upgrade the SD18 with computers (SD18-3?) but it's still going to be a fuel hog compared to the GS.