Reihe 4000 Big Boy | Gauge H0 - Article No. 37996

Steam Locomotive with a Tender

Controlling the Giant
Who has not sometime wanted to drive the largest steam locomotive ever built on his own, the "Big Boy" from Union Pacific Railroad (UP)? No problem with the new H0 model from Märklin. The built-in mfx+ decoder in the World of Operation mode brings back the operational feel of this giant to your model railroad. There are also 15 different digital functions from the cab radio to the squealing brakes to go with it.

Prototype: Union Pacific Railroad (UP) class 4000 "Big Boy" heavy freight locomotive. Version with the road number 4020. The locomotive looks as it did around 1950.

Steam Locomotive with a Tender
Steam Locomotive with a Tender

Most Important Facts

Article No.37996
Gauge / Design type H0 / 1:87
KindSteam Locomotives
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  • Coolers of the second production run in front of the smoke box.
  • Changes to the headlight.
  • mfx+ digital decoder included.
  • Product description

    Model: The locomotive has an mfx+ digital decoder and extensive sound functions. It also has controlled high-efficiency propulsion. 8 axles powered. Traction tires. The locomotive has an articulated frame enabling it to negotiate sharp curves. It also has Boxpok driving wheels. The middle driving axles are spring-loaded. The headlight, backup light on the tender, and the number board lights are maintenance-free, warm white LEDs. 2 smoke generators (7226) can be installed in the locomotive; the contacts for them are on constantly. The headlight, backup light on the tender, and the number board lights will work in conventional operation and can be controlled digitally. The cab lighting can be controlled in digital operation. There is a powerful speaker in the tender and the volume can be adjusted. Coupler hooks can be inserted in the pilot on the front of the locomotive. There is a close coupling between the locomotive and tender. Steam lines are mounted to swing out and back with the cylinders. The locomotive has separately applied metal grab irons. There are many separately applied details. Figures of a locomotive engineer and fireman for the engineer's cab are included.
    Length over the couplers 46.5 cm / 18-5/16".
    The locomotive comes in a wooden case.

    The image of this model is a retouched digital image. Notes for operating this locomotive: The locomotive can be used on curved track with a radius of 360 mm / 14-3/16" or more, however we recommend larger radii. Due to the overhang of the long boiler, signals, catenary masts, bridge railings, tunnel portals, etc. must be installed for sufficient clearance on curves. The track must be well mounted due to the heavy weight of the locomotive. The locomotive can only be run through a turntable or transfer table. Products bearing "Union Pacific" are made under trademark license from the Union Pacific Railroad Company.

    Car sets to go with this locomotive can be found in the Märklin H0 assortment under item numbers 45659 and 45660. This model can be found in a DC version in the Trix H0 assortment under item number 22063.

    One-time series.

  • Publications

    - New items brochure 2015 - Product programme 2015/2016
  • Digital Functions

    Control UnitMobile StationMobile Station 2Central Station 1/2Central Station 3/2*
    Mobile Station 2**
    Smoke generator contact
    Steam locomotive op. sounds
    Locomotive whistle
    Direct control
    Engineer’s cab lighting
    Warning Sound
    Sound of squealing brakes off
    Air Pump
    Auxiliary Blower
    Sound of Couplers Engaging
    Rail Joints
    Operating Sounds 2
    Cab Radio

    * New features of the Central Station 2 (Part No. 60213, 60214 or 60215) with the software update 4.2

    ** New features of the Mobile Station 2 (Part No. 60657/66955) with the Software Update 3.55

    Find more Märklin explanation videos on our YouTube Channel


ATTENTION: adults only