Union Pacific DDA40X Centennial  

2:55 Cannot beat the sound as those EMD 16-645E3A engines power up. A very iconic locomotive sound.

This engine is currently on display in N. Little Rock. It's an awesome engine, the size is unbelievable. As a model railroad enthusiast I have this in my collection, but to see it in person is great.

Just listening to that EMD power is the best sound that an engine could produce.

The 6936 was designed to run intermodels at high speed. Working heavy freights at slow speed would damage the traction motors, that is why AC units have been such a success. SP ran a heavy train over Tennessee Pass using six AC4400s and speed fell to 1 mph but the ACs kept going. A lashup of DC traction motored units would have had most of its motors burn out. That is why Railroads use mainly AC units for heavy hauls. Hope this info is of help.

2:58 throttling up sound here is terrifyingly haunting it is just so powerful - there is NO other unique sound like it in the entire world. I'm a Kiwi [New Zealander] and we love our trains over here, however there is simply no locomotive anywhere near as powerful as this DDA40X Centennial #6936. Our most powerful diesel-electric locomotive was the General Electric GE DX class [nicknamed 'Dixies'] and its prime mover was the General Electric 7FDL-12 [Turbocharged V12] that put out 2,240 kW (3,000 hp) with a tractive effort of 259 kN (58,000 lbf) - not too shabby for New Zealand. There was a total of 49 built from 1972-75 and in service throughout NZ. There are 2 sub classes DX-'B' & 'C'. In 1993 another sub class was re-built DX-'R'. In mid-2018, it was announced 15 DX class locomotives were to be overhauled, and given an electronic upgrade. 3,300 hp-rated GE 7FDL-12 EFI diesel engine prime movers with electronic fuel injection. They were also be given the latest version of the Brightstar engine control system, new engine control and wiring harness, and new high capacity fuel tank, along with a new battery box assembly. They were classified as DX-'E'. As of 2021, only two DX class locomotive had been withdrawn from service!

Awesome seeing it still running and UP is using it as it was meant to. Epic

Both my grandfathers worked for the railroad and I lived right by the tracks. I remember seeing old switchers and these centennials rumble by the house. I used to have plenty of time to run outside and see them before they came, because the house would rattle and the signal on the old crt TV would go out when it was blocks away it was so violent and heavy. Im 41 now and still into trains. Both my grandfathers passed right before they announced big boy 4014 was being restored. Man I wish they could see them under steam again. We always talked about it probably never happening again but they would take me to the Forney museum in Denver to see the old big boy.

Awesome video! It's neat to see the UP #6936 out in freight service.

Incredible beast centennial

Ahh nothing like a EMD DD40AX. Its still the most power single diesel unit in the world.There are diesels that UP and CSX have that make 6000hp and there are others around the world but I haven't seen any recent diesel that tops the 6600hp mark. Awesome video!! I have 3 of these in HO scale along with two DD35A units, the predecessors to the DD40AX units. Awesome pure Awesome!!

Awesome! You never realize how big they are until you see it in person.

A legendary locomotive

Brings back the spring of 1969, heard about the big sister to the DD35s from the news articles in TRAINS mag. Never got to see one live, living in Milwaukee, WI.

Awesome video! Loved hearing the twin 645's notch up at 2:59 - 3:24. Thank you for making my day!

I wish it would have been the lead unit. Happy railroading!! Gary

What an absolute unit.

Those Centennials were awesome. Some are on display around the country and some are in great condition and in short order, be made operational again.

Hell Yeah Big Daddy DDA40X Awesome Video thank you for posting it

Nice video. I believe that's the most powerful diesel unit ever built...very cool to see one still in service.

Those DDA40 were amazing units. My personal Favorites were the ones in the old Burlington Northern "mean green" paint scheme, but this one in "lemon bolt yellow" is stunning. I can't believe they only made 28 of them and only 25 were actually sold.

There's nothing like that sound of a DDA40X! By far it's EMD's greatest diesel locomotive. The first three Centennials, #6900, 6901, 6902 that rolled out of EMD's assembly line were rated at 7,000hp but drank up, gobbled up all of that diesel fuel, Union Pacific sent them back to EMD to change out their fuel injectors which dropped the horsepower to 6,600hp at the rail...

Catch of a lifetime!

DDA40X is a Limo of a Locomotive. I Love the sound of SD40-2's, SD45-2T's, SD50's and EMD's in general!

Once again I find out something has come through my home town and I never know about it....first it was 844 now its 6936

Awesome video! What a beautiful locomotive!

You were lucky to see this. thanks for the view.

Nothing is better than the world's largest & strongest diesel locomotive Except big boy ❤️ Love you big boy ❤️

Wow, i Love the DDa40x. So huge and powerful. Awesome!! These shots are very rare :)

Its good to see it back in freight service

It's good to see it doing what it was designed to do.

Nice seeing this old thing still used!

That's just downright awesome! Great catch!

2 dirty UP locos pulling a clean unit

I was at the Illinois Railway Museum last week and saw one there. That thing is absolutely humongous. I couldn't believe how big it was.

Unbelieveable how large that locomotive is.

The *Big Boy* of diesels

Great shots here, I love the close ups of the Locomotives.

wow you are so lucky to see that working!!!!

So i hear in this video shes not being just towed shes actually running and MU in the consist which is badass. UP has a list of all their current roster locomotives in the Special Instruction book that we get yearly and the DDA40X and the EMD E9s are still listed as usable locomotives and has all their specifications

6936 sure is a monster

The covered hopper express. That third locomotive pulling that train is a beast.

Now that's something you don't see everyday!

Great catch! The first time I saw 6936 was back in 2006 with 844, 1988, and 1982.

Nice catch, thanks for sharing

Think Big in the USA,Wow amazing ❤️ Fabulous Workhorses ,God bless the Centennial Locomotive,Some size of a beast of a loco there 🇺🇸🇺🇸🇺🇸🇺🇸

Wow, That is a beast of a locomotive!! never heard or seen such a thing!! great catch!!

Excellent training. Cheers!

wow love seeing that big old DD...i'm a little late catching this video...lol

This DD40ax has had more miles being towed

Hello 844 train 6936 thats one hell of a Locomotive

Great catch!

Now hopefully it stays in freight service for a very long time I'm still needing to catch that historical heritage unit. Awesome catch

Imagine if UP ran 6936 here along with the Big Boy... 😯

I was working at EMD - LaGrange when these monsters were built. Consider the problem of moving a 103 foot long (over the coupler pockets) locomotive down an erection bay where the columns were only 100 feet on-center. There was a lot of transitional technology in these units and they really didn't work out that well. They were a dispatcher's nightmare because even the UP had only a few turntables that could turn them and they were just too long for most wyes. Even the UP had limited mileage of track that could tolerate the long trucks. The air filtration was poor, and they ate power assemblies. They rode rough and the crews hated them. They were not as fast as you'd think as they had 88 MPH gearing. Two SD-40s were marginally better and when SD-40-2s came along the DDa40 was dead. Maybe somebody could take them on as an engineering project. Those eight-axle truck castings are national treasures. Single engine (around 4,000 HP), convert to AC transmission and have a good freight locomotive for straight runs. They seem to be in salvagable shape.

Such a sweet engine. Too bad they couldn't kept more in service.

excellent video

Awesome catch!

Wow, weird to see that big engine back in regular service. Isn't that the locomotive (6936) that would be in the consist with the 844 when it traveled around the country? I was trying to figure out why the 6936 was put back into freight service after all these years.

I love how all the other engines are dirty and the dd40ax is clean like u.p wants it stick out like a sore thumb.

@02:57, best part. Super video Chris!

Great video!

This video is very well done, outstanding. The DD-40's actually had more horsepower than this when they were introduced back in 1964,these originally were known as DD-35's but they reposition the fuel injectors for better fuel efficiency on the twin V-16 diesel engines.The final version of these engines were running at 3,300 horsepower apiece in one unit.They started with about 3,500 apiece at first.If they would have stayed with this engine,which is basically the same engine in the SD-45,it would have been 7,000 horsepower in each unit!!.

Amazing Catch!

Excellent catch with the rare monster DD40AX trailing in the consist!

Great video...Thanks for sharing.

Nice man...Nice comparisons with the GE 44 and SD 70Ace. I always wondered how long they were compared to Big Jack..LOL.

The two GE's must have felt the centennials strength as it is really a strong engine

It’s a monster for sure💪

Nice video!

Wonder if I hear this beast in middle of the night here in eastern Washington. We get some trains coming through that rumble my walls from miles away while coming into town.

I can only imagine what they would look like back to back hauling freight

I wish that Kato would build a"N"scale DD-40EX with dual motors and 4 flywheels.

6939 to the 2 lead units: Too Eazy. Yall wait till you got a freight that need trouble and happens to be nearby 4014. Tbf that would be a EPIC site seing 4014 hauling a monster freigt up that hill.

NICE VID. I was able to get some pics. from the 10th street bridge but i didn't get there in time to see it moving.

LOVE the thump of those Diesels...

Fuck union pacifiac wakes me up 6 to 7 times a night

The dd40ax is a nice looking locomotive that Union Pacific made

There's one in chamberlain sd. Sadly it's been stripped down and think it's only over for fuel storage now

Awesome Video

Nice to see

it's the diesel equivalent to the Union Pacific big boy

1:00 the DDA40X 6936

I don’t like UP but he DDA40X WAS SUCH AN AWESOME LOCOMOTIVE ,but I wish they would help restore some of the STEAM LOCOMOTIVES FROM THE COMPANIES THEY MERGED WITH. I THINK IT WOULD HELP THERE IMAGE TREMENDOUSLY

I had no idea any were active.

Nice find!

Awesome. I have to say though that the Centennials are designed for faster trains than slow unit freights.

Nice!

Nice video Chris!

The yellow sill stripe is fugly (who cares about the FRA "rule", this is a piece of history).

Woulda been cool if they made a version with a full width carbody and f unit bulldog noses on both ends.

18k views on this, since Spring. Looks like you got a popular video!

I'm sure it's just being towed here. Still great to see with the other units on a freight train. I saw this engine leave Denver Union Station pulling the Cheyenne Frontier Days Special in 2000. It was a last minute replacement for the Challenger which had a mechanical issue. Believe me, when this thing pulls, it smokes.

I want to see more of these locos

Hay una aqui en la Ciudad de México una EMD DDA40X en el Museo Papalote del Niño en Chapultepec

Also, the 6930 at the Illinois Railroad Museum can be mued to other locomotives.

Man, that is one big boy. Wait...

! Nice video, Like

love the 3rd shot :)

That DD40 isn't running, it's just being towed. Starting at about 2:45 when the units throttle up, you clearly see smoke from the lead two units and not the Centennial. Still, nice video of one of the great diesels that ran on our nations rail!!!

Man oh man, how I hate that sound of a diesel horn. The steam whistle is music to my ears, but sure rare these days.