TECHNIC / 42242 · REVIEW

LEGO Technic 42242 Mercedes-Benz Unimog: Great to Look At, But Where Has the Technic Gone?

The Unimog is one of those vehicles that seems almost made to become a LEGO Technic set. Mechanics, suspension, transmission, equipment and countless possibilities for customization: on paper, it has practically everything needed to create a particularly interesting Technic model.

And that is precisely why the LEGO Technic 42242 Mercedes-Benz Unimog, with an official LEGO price of €119.99, comes with fairly high expectations.

After all, the Unimog is no ordinary vehicle. It was designed as an extremely versatile machine, essentially a chassis and cab that can be fitted with a wide variety of equipment and configurations. In the version recreated by LEGO, we get a crane for lifting loads and a rear tipping bed.

In other words, a perfect subject around which to build plenty of mechanical functions.

The problem is that once the model is finished, I am left with almost the opposite impression: the functions are there, but hardly any of them completely convince me.

And that is where the problems begin.

Visually, the Unimog Works

Let’s start with the positives.

The model is immediately recognizable, its proportions are convincing, and the large tyres give it the substantial, rugged appearance you would expect from an Unimog.

The cab is nicely represented, the bonnet can be opened to reveal the engine, and the doors can also be opened. Overall, once completed, the 42242 is certainly a model that looks good on display.

But for me, that cannot be enough.

Because we are talking about LEGO Technic.

And a Technic set should become especially interesting when you start moving it, operating its functions and, above all, understanding how it works.

Everything Is Manual — and There Is No Real Provision for Motorization

The first thing that stands out is that every function is manually operated.

There is no motor included, of course, but more importantly, the model does not appear to have been designed with any real provision for adding motorization later.

Even the pneumatic system lacks the small cylinder that, in other systems, can be connected to an eccentric mechanism and a motor to create a small compressor.

There is no motorized drive, no motorized tipping bed and no officially designed solution for automating the various functions.

Of course, you can experiment. I tried looking into motorizing the rotation of the crane, connecting a motor to the axle that drives the worm gear mechanism. Technically, it can be done, but the motor ends up sticking out of the model, so you then have to come up with a solution from an aesthetic point of view as well.

And that is exactly the point: I am not saying LEGO necessarily should have included motors and electronics in the box, inevitably increasing the price.

I would simply have liked to see some provision for motorization built into the design.

A Technic model should almost invite you to modify it, experiment with it and add new functions.

Here, that feeling is missing.

The Tipping Bed: Simple on Paper, Much Less So in Practice

One of the main functions is, of course, the rear tipping bed.

The system uses a relatively simple solution involving a worm gear, another gear and a series of linkages.

The problem appears when you actually use it.

Turning the control wheel begins to raise the bed normally, but at a certain point you reach a position where a considerable amount of torque is required to overcome a critical point in the mechanism.

Once past that point, the movement becomes easier again.

But overall, it is anything but smooth.

The system relies heavily on the geometry of its linkages and, while operating it, you get the feeling that the mechanism almost has to be “forced” to complete the movement correctly.

The tailgate also requires manual intervention: the friction of the pins does not allow it to drop convincingly on its own while the bed is tipping.

So yes, the function is there.

But the fact that a function exists does not necessarily mean that it has been implemented well.

The Pneumatics Are There, But Smoothness Is Not

The crane uses two pneumatic actuators and, at least on paper, this should be one of the most interesting parts of the model.

Before using it, you need to manually lower the two stabilizers, which help support and stabilize the vehicle while operating the pneumatic pump.

The crane can then be controlled through two valves operating the respective cylinders.

And this is where one of the most obvious problems appears.

The pneumatic system offers very little control over the movement, especially when the actuators are retracting.

Simply moving the valve lever can cause the piston to react very suddenly, effectively moving in jerks.

The result is a movement that does not look particularly realistic.

And on a working vehicle such as the Unimog, where moving loads should be one of the most satisfying features, that is an important limitation.

It becomes even more noticeable when you actually try to use the crane to hook the platform and load it into the tipping bed: controlling the movement precisely is far from easy.

I am not criticizing the basic idea of LEGO pneumatics, which remains interesting to build and experiment with.

I am criticizing the result I get on this particular model.

A crane should allow me to control a load with a reasonable degree of precision. Here, especially when retracting the actuators, that precision is almost completely lost.

The Crane Rotation Works, But It Is Very Slow

The crane can also rotate.

Here we find a large gear driven once again through a worm gear.

The mechanism works, although the rotation is inevitably very slow.

For this kind of function, that is not necessarily a major problem. It is certainly not the aspect of the model that bothers me most.

But it is another example of fairly basic mechanics in a set where, considering the subject matter, I expected something more sophisticated.

The Steering: Why Complicate Something That Already Worked?

Then we come to what I consider another weak point of the 42242: the steering.

LEGO has not used the traditional rack-and-pinion solution. Instead, the steering relies on a system of linkages.

Experimenting with different solutions is not necessarily a bad thing. In fact, with Technic, it should be one of the most interesting aspects.

Provided, of course, that the alternative solution works well.

Here, I personally cannot see the advantage.

The steering is not particularly effective, the steering angle is very limited and, considering the overall weight of the model, operating it does not feel especially satisfying.

It is one of those cases where I keep asking myself:

why?

Why choose an alternative to a conventional steering rack if the end result is less effective?

Being technically different does not automatically mean being technically better.

An Interesting Engine, But Something Does Not Move as It Should

Under the bonnet we find another interesting solution.

The piston movement is created through a kind of camshaft system, using small elements that interact with wheels mounted eccentrically.

It is an interesting solution and visually it works: when moving the model, you can watch the sequence of the pistons through the opening bonnet.

The problem is that on the model I built, I noticed some rather strange behaviour.

When moving the Unimog backwards, the engine turns reasonably well, while pushing it forwards causes it to almost seize up.

I cannot say with certainty whether this is an issue specific to my copy, a matter of tolerances between some components or an inherent characteristic of the design.

But the behaviour is there, and I cannot ignore it.

The Suspension Is Not Entirely Convincing Either

The model features a differential and suspension on both the front and rear axles.

Another feature that, simply reading the specifications, sounds absolutely positive.

In practice, however, the result leaves me somewhat unconvinced here as well.

The suspension is very stiff, and its effective travel is limited. The weight of the model and the preload on the springs may have influenced some of the design decisions, but the end result is still a system that I find rather ineffective.

The construction of the front and rear axles is interesting to examine, but once again I am missing that mechanical feeling I would expect from a vehicle like this.

And inevitably, my mind goes back to another Unimog.

We will get to that one shortly.

Part Quality and Tolerances: Something Left Me Perplexed

During the build I also encountered something that, personally, does not happen to me very often with LEGO.

Some elements felt unusually loose, offering very little grip, while others required considerably more force than expected to insert.

These differences in tolerances are something I have generally encountered more often when working with compatible building systems than with genuine LEGO elements.

That does not necessarily mean that every copy of the set will have the same problem.

But I encountered it on mine and, considering the level of quality we have come to expect from LEGO, it left me rather puzzled.

That “Rubbery” Feeling of Modern Technic

Then there is a more general issue, one that goes beyond this particular Unimog.

And it is probably one of the reasons why I find it increasingly difficult to get excited about some modern Technic sets.

Older models used a greater number of traditional studded elements, naturally combined with pins, axles, gears and Technic structures.

Today, much of the construction relies instead on panels, studless elements, pins and structures that sometimes almost seem to be “hanging” from the chassis.

The result is undoubtedly cleaner from an aesthetic point of view.

But when handling the model, I often get an almost rubbery feeling, less precise and less solid than what I remember from Technic models of the past.

Even on this Unimog, some elements used to create diagonal lines are simply positioned at an angle rather than being firmly locked into place.

Every time you handle the model, they can move and need to be realigned.

These are small details, certainly.

But added together, they contribute to the impression of a construction that feels less robust and less “engineered”.

And for a Technic set, at least for me, that is a problem.

Some Aesthetic Details Could Have Been Better Too

There are also a few secondary details that certainly do not ruin the model, but are worth mentioning.

The mirrors, for example, cannot be angled into the position I would expect: they can rotate, but essentially remain very wide in relation to the cab.

There are also visible yellow and red axles in several places, something I personally continue to find rather inelegant on a model that is also intended for display.

And then there is the green.

It is a colour we have already seen, for example, on the Lamborghini Sián, and here too I noticed a certain lack of colour consistency between different types of elements: panels, connectors and other parts do not always appear to have exactly the same shade.

It is certainly not the Unimog’s biggest problem, but it contributes to the overall impression of a product that could have benefited from a little more attention.

And What About the B-Model?

On top of all this, there is another omission that carries quite a bit of weight, especially for anyone who has been building Technic for many years:

there is no B-Model.

By now, we have almost become accustomed to this.

But that does not mean it is a good thing.

For years, one of the most interesting aspects of LEGO Technic was discovering that the same collection of elements could be used to build a completely different second model.

It was not simply extra content.

It was part of the philosophy of Technic itself.

Take it apart. Rebuild it. Discover another solution.

It dramatically increased the longevity of the set and, more importantly, demonstrated just how versatile the building system could be.

On a model priced at €119.99, I still miss it considerably.

Then You Think About LEGO Technic 8110…

And here we inevitably arrive at the elephant in the room.

Because if you say LEGO Technic + Unimog, anyone who has followed the theme for a while will immediately think of one number:

8110.

The LEGO Technic 8110 Mercedes-Benz Unimog U 400 is, for me, simply an epic model.

Of course, a direct price comparison with the 42242 would not be fair: these are sets from different eras, with completely different sizes and market positioning.

But the point is not which one cost more.

The point is how much each model offered for what it asked from you.

And from that perspective, I still have the feeling that the 8110 offered considerably more.

It was big, complex, packed with mechanics and, above all, it gave you that wonderful feeling that you were building a machine, rather than simply an aesthetic representation of a vehicle.

Even the suspension had a behaviour that I still remember as one of the most interesting aspects of that model.

You could turn it upside down and still find something to observe, understand and study.

The 8110 perfectly represents what I mean when I say:

when Technic was still truly Technic.

I do not want LEGO to keep recreating models from the past.

But I would like to see that same design philosophy again.

From Building Machines to Display Models?

And this is probably the real point behind my criticism.

In recent years, Technic seems to have moved progressively closer to the concept of a display model, with increasing attention being paid to licences, bodywork and making the subject instantly recognizable.

Supercars, panels, increasingly elaborate shapes and models designed, above all, to look good on a shelf.

There is nothing inherently wrong with that.

But when aesthetics begin to replace mechanical experimentation, I start wondering what really distinguishes Technic from other LEGO themes dedicated to vehicles.

Because one thing should be clear:

these models exist to be Technic.

If the technical side is precisely the part that convinces me the least, then we have a problem.

And ultimately, that is my main criticism of the 42242.

Not that it looks bad.

Not that there are no functions listed on the box.

But that several of the functions it does have are simply not particularly effective.

The tipping bed is difficult to operate.

The pneumatic actuators move too abruptly, especially when retracting.

The steering system without a rack has limited travel and does not convince me.

The suspension is very stiff.

On my particular copy, the engine movement is inconsistent depending on the direction of travel.

And all of this comes on top of the complete absence of any real provision for motorization and the lack of a B-Model.

It is the combination of all these things that creates the disappointment.

But It Could Be a Very Good First Technic Set

Having said all that, there is one important aspect to consider.

Your opinion of the 42242 may change considerably depending on who is approaching this set.

For someone looking to enter the world of LEGO Technic for the first time, the Unimog could actually represent a good entry point into the theme.

It is not an overly basic model, but at the same time it does not require you to immediately tackle one of the huge, expensive and highly complex Technic sets.

There are gears, linkages, pneumatics, a differential, suspension, a working engine, steering and several functions to build.

For someone who has never experienced a more involved Technic model, there is therefore quite a lot to discover.

And the subject itself is certainly appealing.

From this perspective, I can understand the 42242 much better: it could be the right set for someone looking at Technic from the outside who wants to try something more interesting than the entry-level models without immediately committing to a huge build.

For someone who has been building LEGO Technic for years, however, the situation is very different.

So, Is It Worth €119.99?

Personally, at full price I expected more.

The LEGO Technic 42242 Mercedes-Benz Unimog looks good, provides a reasonably involved building experience and includes enough mechanical elements to make it interesting, particularly for someone discovering the theme.

But at €119.99, I find it difficult to ignore all the compromises that become apparent once you actually start using it.

If you want to add it to your collection, perhaps because you collect Unimogs or simply because you particularly like the vehicle, I would personally wait for a worthwhile discount.

For those who have known Technic for many years — and perhaps still remember a model like the 8110 — it is difficult not to expect something more.

Is it ugly?

Absolutely not.

Does it lack interesting ideas?

Not at all.

But it disappointed me.

And that is an important distinction.

The 42242 can be a good first Technic set for someone who wants to discover the theme while already moving beyond its most basic models.

For those who know what Technic has been capable of, however, the overriding feeling is one of a missed opportunity.

Because ultimately, the 42242 is a good model of a Mercedes-Benz Unimog built with Technic elements.

I simply wish it had also been a great LEGO Technic set.

Great to look at. Interesting to build. But this time, for me, that isn’t enough.