The first thing I thought when I saw this set announced was: Yet another crane. And indeed it feels like cranes return nearly every year in Technic form. Does this set offer anything new?


The Set
The Box
The Instruction
The Parts
The Build
Bonus: Alternate MOC Review


So, yet another crane... That was my first thought when I saw this set announced. But when I started to search for crane sets, I was surprised I only found 19 sets in the 42 year history of Technic. And in the same style as the 42108-1 there are only 11. They also range from 218 up to 4056 parts, so there seems to be some variation. Going by part count, the only one that comes close is the 8053-1 - Mobile Crane from 2010. And while I have multiple of the cranes, I'm missing that one for a good comparison. And comparing it with recent models like 42082-1 Rough Terrain Crane with 4056 parts, or the 42009-1 - Mobile Crane MK II with 2607 parts would not be a fair comparison. So my tactic for this review will be to just look at the set in itself. Is it fun to build, how are the play features, and does it look nice.

SIDENOTE: The 42009-1 Mobile Crane MK II has a special meaning for me. When the set was released, I was searching reviews for it, and stumbled upon a website called Rebrickable, that had one. That was in a time I didn't even know the term MOC, or BrickLink... At the same time, Peeron.com stopped updating, so I was in need of a new place to keep track of my collection. Fast forward to 2016 when I fell into a depression, lost my job and had a lot of free time on my hand, so I offered to become an admin. And now, I spend most of my free time here.

Here are all results that come up when you search 'Crane' under Technic sets:

The Set

An action-packed set for crane toy fans. Anyone who loves discovering how mega-machines work will have lots of fun with this LEGO® Technic™ 42108 Mobile Crane. It’s a challenging build, perfect for LEGO Technic fans looking for a model packed with functionality. A feature-packed crane truck for construction site fun With its classic black and yellow design, this model looks just like the real thing. And with a mighty range of realistic features, it operates just like a real crane too. First, steer and drive the vehicle to the right spot. Then use the outriggers to secure the crane in place. From the crane cabin, raise the boom and extend the telescopic arm – see how high it reaches! Then use the hoist to carry the concrete pillar – great for role-play, or just for testing what this mega-crane can do. An immersive and rewarding construction site toy This is a challenging and advanced build from the LEGO Technic universe, bringing the world of engineering to life.

The Box

The box measures 34.8 x 37.3 x 10.4 cm, and weighs 1910 grams. Inside are 10 bags numbered 1 through 3, a bag with tyres, and the building instructions and sticker sheet in a foil pack.


The Instructions

The instructions measure 27 x 19.2 cm. There are 436 building steps on 271 pages.

The pdf can be downloaded here.

The Parts

The set contains 1292 parts and 14 spares, in 15 colors, and 23 part categories, with a total of 145 unique parts/color combinations.
Main colors are:

Main categories are:

There is one part in a new color:

There are a few parts in rare colors:
11954 Technic Panel Curved 11 x 3 with 10 Pin Holes through Panel Surface previously only appeared in big brother 42009-1. This set has 11 of them.

14720 Technic Beam 3 x 5 Thick [90° Offset Centre Beam Holes] appears for the 3rd time in Yellow since 2019.

40918 Technic Linear Actuator with Dark Bluish Gray Ends Long previously only appeared in 42100-1.

37597c300 String Cord Medium Thickness 300cm only appeared in big brother 42082-1 before.

The Build

Bags 1 build the chassis and start the cabin. What I love in Technic, is that you start something that makes you wonder: What will this be used for. I had that with these 2L beams. Turns out they control the steering.

We end up with a chassis that is basically some 64179 - Technic Beam 5 x 7 Open Center Thick with supporting beams and a steering mechanism build around it. Some may call the seats cheaply done. I call it not wasting parts on looking pretty, but saving it for the functions.

Bags 2 finishes the cabin and starts the upper structure. I like the simple but effective design. The flash lights on top work as HOG steering.

Bags 3 add the liftarm and some bodywork.

This is the first time I see a sticker on a 14719 - Tile 2 x 2 Corner. According to Bricklink, this has happened before.

In the back is room for a motor and some gear shifters. On the side would fit a battery box. Get your MOD on!

There are 2 levers preventing the liftarm and pulley to collapse under load.

And lastly, there is something to lift.


This was a joy to build. No, it's not as big and complex as the 42082-1, but that is not what you must expect here. For a set in this price range and part count, the designer did a great job. The previous Technic sets I build where the 42100-1 - Liebherr and 42110-1 - Landrover Defender. And I must say it was nice to build something more straightforward. Nothing too complex, no wasting time on little details. It felt almost as a relief.The functions all work smooth.
For who is this set: Beginners that are looked out on the smaller sets, AFOLs that are looking for something 'in between' larger sets, or people that use it to feed MOCs.
My daughters (9 & 8) weigh in as well: They like the fact that the model is not motorized. At first they were dissapointed, but then they found out, that by controlling the model by hand, you have better control and can see what is happening along the drive trains. It is much more engaging than flipping a switch.
Is it all perfect? No, there are some minor things to mention. The wire on the head of the liftarm repeatedly came out of the pulley, especially in horizontal position. And the top of the upper structure could use some coverage, especially with the nice finish on the sides and the back, this looked unfished.

Bonus: Alternate MOC review

While writing this review, I was checking if there were any MODs or alternate builds for the set. At that time, there were none, but I found a new submission in the admin screen. Seeing Rebrickable is all about re-using your bricks, I've build this model as well. The MOC is designed by Taurus Creations and can be found here.

First thing I noticed, is that the MOC uses 1230 parts of the 1292 parts from the original set. That's a nice high percentage, and in my opinion something to be desired in an alternate.

The steering is similar to the main model.

Here there front and rear are done, giving an indication of the size of the truck.

There are a few instances where the order of the build could be optimized. Here for instance it would be better to first build the entire wheelarch, and then attach it to the main model. But it's never a real annoyance, and doesn't harm the build experience.

The finished truck.

See here why I don't like applying stickers. It disrupts MOCs.

Then the trailer gets build. Everytime I see this rear with these blue fenders, I get a beach buggy or trike vibe.

The trailer without the crane. The outriggers are clever little mechanisms.

Wires are always tricky in digital instructions. This is well solved by the designer with some extra drawings and directions.

All the leftovers.

The completed build.

I'm impressed by how well this model looks and functions. Of course there are some small flaws, but that is all minor stuff. The build is not as sturdy as it could be, but that is because the limit in parts availible. There is a lot of thought and effort put into this design. The building instructions are well done, with 535 building steps. This is not a designer that just wants to earn a quick buck. He puts in the needed effort and delivers quality.
The short conclusion is: Well worth your money!

Disclaimer: This LEGO set was kindly provided for review by The LEGO Group. Anything said in this post is the opinion of the author and not The LEGO Group. The instructions for the MOC were provided by Taurus Creations.
Parts- and build photographs by Tobymac (© 2020 Rebrickable)


  • 1 week, 5 days ago 13neat8 Level 17 MOC Designer PRO
    Thank You for the review TobyMac! I think I‘m going to buy one of those.
  • 1 week, 6 days ago Lego-holic Level 7
    Great review and send a thanks out for your daughters for their input as well . . . . maybe they'd team up for a review someday ;)
    And because of that, this one will be on the list for me and my 10 year old son. Thanks again.
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