Technic

All-Terrain Vehicle

A little forestry beast that packs more working functions than sets twice its size.

Brick Rated Score

3.8/5

Set 42139 · 2022

Pieces764

Minifigsn/a

Year2022

Set number42139

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The verdict

I went into this one expecting a fairly plain 10+ Technic filler and came out genuinely charmed by how much LEGO crammed under the shell.

Steering, suspension, a two-cylinder engine, a proper little 1-neutral-2 gearbox, a winch, a tipping bed, and a chainsaw whose chain actually spins. It is honestly a small engineering education in a box. The catch is the looks and the price, so this is for someone who cares far more about how a model works than how it poses on a shelf.

Best for: Curious builders who want to understand how a real gearbox works without committing to a giant flagship Technic set

The full review

What it is

The All-Terrain Vehicle is a six-wheeled forestry hauler built to teach you how mechanisms work, and the first time I ran through its gearbox I understood exactly why people who bought it ended up liking it more than they planned to. This is a 764-piece set aimed at builders 10 and up, but the instruction booklet is thick because there is so much going on inside. You start with the gearbox itself, lining up gears and pins, and it is fiddly in the best way. When it finally clicks together and you can flick a lever to shift between first, neutral, and second, it is one of the more satisfying moments I have had in a mid-size Technic set. From there you add a two-cylinder engine with moving pistons, front steering, suspension, a winch, and a rear bed that tips.

The catch

I will be straight with you about where it falls down, because the criticism is fair. The colors are the big one. There is red running all through the chassis where it really should have been saved for the control surfaces, and the blocking is poor enough that it can be hard to tell one section of the vehicle from the next while you build. Several reviewers called the finished thing a bit of a mess to look at, and I understand why. Then there is the price. This launched at around 90 dollars for fewer than 800 pieces, which is steep, and for a parent standing in a shop that number is going to sting next to a chunkier set. There are also no new parts and no recolors here, so if you collect for the elements you will not find anything to get excited about, and it relies on a fairly large sticker sheet.

Who it's for

So who is this actually for? If you or the person building it loves understanding how machines work, this is a small joy, and I think it is one of the best gentle entry points into Technic that LEGO has made. The gearbox alone teaches more than a whole shelf of pull-back cars. If you want a model that looks sharp displayed on a shelf, or you measure a set purely by piece-count value, this is not the one, and you will feel the price. It has now retired, so it is aftermarket only, which makes the value question even more personal. Buy it for the mechanisms and the build, not for the finished silhouette.

The parts story

What the build is actually like, and the pieces worth knowing about.

Building this is a lovely lesson in cause and effect. You spend the opening stretch assembling that gearbox, carefully seating gears and pins, and it is the kind of section where you slow down and pay attention. Once the drivetrain, engine, and axles come together, half the fun is turning the wheels and watching the pistons pump and the winch spool. The two rear axles connect to the front through turntables so they pivot independently over bumps, which gives it real character on uneven ground even though the body itself does not bend side to side. It took me a solid few hours, and none of that time felt like padding.

On the parts front there is honesty to be had: there are no new molds and no recolors in the box, so nothing here will make a collector gasp. What you get instead is a well-chosen pile of Technic gears, axles, connectors, and panels that all earn their place driving a function. The standout accessory is the chainsaw, a genuinely fun little build whose chain rotates around its bar, paired with 20 small log elements that clip together into larger logs. For a set this size the sheer count of working sub-assemblies is the real value, even if the raw piece-per-dollar math does not flatter it.

Fun facts

01The chainsaw that comes with it is functional, with a chain that actually rotates freely around its bar.
02It packs steering, suspension, four-wheel drive, a two-cylinder engine, a two-speed gearbox, a winch, and a tipping bed into under 800 pieces.
03The two rear axles attach to the front section through turntables, letting them rotate independently over rough terrain.
04It launched in 2022 with an RRP around 89.99 dollars and retired at the end of 2023.