Some of the video comments are enlightening:

"@werhaski8158" reported 7 days ago the same problem with derailment of the front wheelset on the slim turnout on the C track. The middle front wheelset is spring-mounted and protrudes slightly. The slightest unevenness on the points, e.g. if they are not flat, or the slightest unevenness the track, especially in tight radii, have levered the front wheelset out of the guide. He has leveled two places on turnouts and radii, now it runs on all tracks and turnouts without derailing. Moving the points a little can also help. Now it runs perfectly with good traction on tight radii and two helixes.

"paulchensundfranksmodellba8756" reported 12 days ago that there is an extremely strong spring under the bogies to press the chassis onto the rails. Having shortened this spring, a lot of removal work is necessary, so the bogie is more flexible and adaptable to small bumps. After the intervention the locomotive runs perfectly over all turnouts.

"JeremyCRunge" reported 12 days ago that the front truck fell off when unboxing the loco. After reassembly the loco ran well on R1 curves, but it derailed on a turnout, too. Dissassembling the truck, he saw that one of the small clips that holds the axle in the correct position was not clipped in correctly. A test run after fixing the clip resulted in the loco mastering again R1 curves, but the turnout derailments continued...

"railwaysinh0771" reported 13 days ago the same problem with the turnout. In his opinion it is because the bogies have enough play on the line parallel to the track up and down, but almost none on the line perpendicular to the track. No problem in the straight position, but when branching off. Having shimmed the turnout a little in the direction of the branch it works now.

One interesting thing here is that, compared to the Broadway Limited version which has all 3 axels powered in each truck, it seems like Marklin has redesigned it with "only" two axels powered in each truck. This is when comparing the exploded drawings......

According to Broadway Limited, Märklin leased the tooling from them.
ref this post: https://www.stummiforum.de/t211171f2-USA-Neuheiten-Maerklin-Trix-H.html#msg2509713
also posted on this forum by Alsterstreek

Yes indeed, and the next user has discovered additional flaws: https://www.forum.hag-in...postID=155231#post155231

Do I really see tension brackets has Märklin developed this model on their own




This is exactly the issue with Scandinavian produced models from China, broken on the first maintenance so let's hope the building up their spare parts storage

Should it start to end like this, no thanks





It is time for Märklin to ensure its so-called quality brand

Jonas, seeing your pictures, it seems to me this does not look AT ALL like a Märklin design. So it may be NO WONDER it does not work on Märklin Tracks
Just a guess on my part, maybe, this is a foreign design of an american loco slightly modified, apparently not thourougly tested on Märklin 3 rail tracks and the protruding Pukos at points
Cheers
Jean

I guess I'm about to find out, my first ES44 arrives today, the second is in transit!

Upon seeing this comment I measured the inner flange on my 38440 ES44 when it arrived today - the measurement was 14.17mm.

Compare that with my 37040 BR 50 which measured at 14.3mm. I've had the BR 50 on my friend's layout pulling a long train through multiple types of turnouts with no issues.

I put the ES44 on a small loop of C track with curved points and also a pair of 24612 turnouts providing a crossover from outer to inner rail. The loco has been running through that with no issues although I did notice the first time around the loco jumped a bit on the front bogie as it went through both set of turnouts. For lap 2 and subsequent ones there has been no issue.

Next test will be pulling some UP hopper cars (not the new ones but the 48500 brown ones).

Bigdaddy,
Just curious. Do you have lanterns on your turnouts?
My MTH 3-rail only passed the lanterns on slim turnouts.

Finally i find the time to run the loco,i had no problem running her forward or backward via turnouts 24611,24612 and 24620 i have to my layout.The loco running perfect to all speeds and have brilliant sounds.The only thing i have to do is to set accelaration delay and breaking delay the way it fits to my layout.

I’ve had problems with switches/points that have the lantern kits installed. A low riding locomotive or rolling stock with come in contact with the lantern to the point of causing a derailment.

Steve

We had a 38440 at the club meeting yesterday. It worked fine on two slim C track turnouts, but had short circuits most of the time on a third slim C track turnout. Exact cause not yet found.
Not my loco, so cannot investigate further.

The loco really looks big when it stands next to a Flying Scotsman.

The issue we saw at our club meeting was most likely caused by a short circuit between centre-rail slider and the crossing outer rail. On slim C track turnouts, those crossing rails are powered and the height difference between rail and pukos is fractions of a millimetre.
If the centre-rail slider slightly tilts to the left or right, it can touch the rail.
Some sliders have plastic bars left and right to prevent that.

I've had 38440 for several weeks now, and 38441 arrived yesterday.

I've ran 38440 around a friend's layout which has many turnouts and curved turnouts and the loco ran with no problems. Two weeks ago we had our Railex exhibition to which we took our Club's H0 modular layout. Unfortunately the loco didn't get very far around the layout but not because of track issues but because someone built a module with a low hanging arch bridge (a non Marklin one) which the loco could not get through through being too tall for the bridge!

It was relegated to yard duties driving between a storage yard and turntable module, which consists of lots of turnouts and a few 3 way turnouts. It traversed everything fine all weekend with no issues.



Shot of the yard part of the layout

Big Daddy, your club layout is mainly wide sweeping curves. As for small plastic parts, Roco was the predominant brand before. Why even attach them to only be lost? With Marklin, it was mostly a buffer,or a little tow hook mounted behind the coupler on the buffer beam.

Jim:
My 38440 can only run on K track.
It cannot run on my metal M track. Loses power on the 5207 double slip switches, and sometimes when I push it, it starts to run, and sometimes derails also.

For K track, I do not use the 2210 small curves on my layout. I do not use the curved turnouts 2267. Removed them from my layout years ago, due to lots of derailing.
Do not use the 3-way turnouts due to problems with derailing.

I do use the high speed turnouts 2271 everywhere else, and they work fine for the 38440.

Please note that I also have the ALCO PA (also 6 axles) made in the early 2000s and they run fine on my metal M tracks due to older type wheel flanges (similar to those in the 3015 crocodile wheel flanges). These do not derail and the larger diameter wheel flanges can pick up the wheel current on the M 5207 double slip switches, and runs right through them.

So I only run the 38440 on my K track. I do not have any C track on my layout. They were commercialized after my layout had already been mostly completed.

Thanks for your feedback Bill.

I am just about to start a new layout and I think that most of the mainlines will be K track, so that is good to know. I have a large amount of C track however which I will be using in less visible areas, so I am also concerned about how these run on C track. I already have issues with some locos on C track turnouts and I really don't want to add any additional problems locos. Most of those problems are slider related and derailments are rare except in those tricky three ways!

I also have an Alco PA loco that is lovely to look at but amazingly noisy, and It does fine running through most of my turnouts. It would be interesting to know if the tracking issues stem from the difference is the wheel flanges, or something about the basic design, which was not made for Marklin track.

I think it depends too on the ramp approach grades. The Vectrons seem to have a lower coupler too.

Responding to Eino in post #33.

I would love to change the wheels. If someone would post the step-by-step instructions as to how to disassemble the wheel assembly to get the axles/wheels out, that would be greatly appreciated.

This model was not designed by Marklin and I do not know which screws to unscrew. There are a lot of screws, and some are covered by the easily breakable plastic detailing parts, and even when the locomotive is placed upside down on a sponge, I am afraid I will break the plastic details on the sides of the lok. This lok is extremely heavy.

Posts #10 and #13 show the bogies opened.

Thou the axle would have to be of the same diameter as the usual Märklin high flanged wheels. The wheels would also have to be of the same diameter in order to fit in to the plastic detailing like brake shoes etc.

The job itself is not a difficult one and all the tools are available from https://www.fohrmann.com/en/ with very affordable pricing.

-Eino

Hi
There is no question that C-Track is way more precise and up-to present day standards.
With a "normal" C-track (not broken, aging track) most of the derailments are caused by things no related to the track.

Here are possible causes:
- incorrect wheel spacing (the track is made for an interflange spacing of 14.0 to 14.2 mm. DC standard call for 14.4 mm which may be the upper limit for Märklin frogs/counter rails
- fine-scale wheels with a narrower rolling surface and smaller flanges may case them to "fall" into the frogs
- stuck mechanism for close coupling: this seldom appears on Märklin goods wagons but is not seldom with long Märklin coaches with provision for surrent-conducting couplers
- track not laid on a flat surface (sometime just a little "hill" or a little "valley" allows couplers to be caught on switches / crossing elevated studs

Cheers
Jean