World's most expensive semi is 4,000HP monster that cost $7M to put together and can drive faster than a lot of cars
Published on Jun 23, 2026 at 3:33 PM (UTC+4)
by Ben Thompson
Last updated on Jun 23, 2026 at 3:33 PM (UTC+4)
Edited by
Ben Thompson

The world’s most expensive semi is a 4,000HP beast that cost $7 million to build and manages to be faster than a lot of cars out there.
The Thor24 is the work of Mike Harrah, who spent seven years building it.
Constructed around the stretched chassis of a 1979 Peterbilt 359, it is nothing short of a marvel in its finished form.
Let’s just say, it’s fitting that this semi is named after the God of Thunder himself, because it’s large and in charge.
Taking a closer look at the world’s most expensive semi
This semi is a total extravaganza, fitted with flames, bright colors and more silver than a cutlery cabinet.
Coming out at 44 feet long and weighing in at 32,000-pounds, there’s no question that the Thor24’s presence is felt on the road.
For creator Harrah, it’s an investment in more ways than one.
Not only did he invest seven years of his life, but he also spent $7 million to make this semi a reality.

Speaking of huge figures, this semi sold for a huge amount of money at auction in Saudi Arabia back in 2019.
Get this – it went for a record-breaking $12 million.
Wowza.
Despite this, the truck remains in Arizona where it was built, Jalopnik reported.
The Thor24 is a real beast on the road
At the heart of this juggernaut is a V24 engine made out of two Detroit Diesel V12s, connected by a crankshaft and featuring 12 superchargers.
All in all, that provides the Thor24 with nearly 4,000 horsepower.
Even Thor’s hammer doesn’t quite have that much power (Marvel fans will no doubt dispute that).

Despite the immense weight of this truck, it can reach speeds of 130mph, which would be impressive for any truck.
But for a truck that’s packing this much gear, it’s truly remarkable.
It’s not just in road performance that the Thor24 impresses either – just have a look at what it’s got going on inside.
This interior of the most expensive semi is nothing short of epic
The original Peterbilt cab has been stretched to fit in some extra doors, and that’s not all that’s different.
All in all, seven movie screens and a 1,500-watt-per-channel 110-volt audio system are enough to win anyone over.
There’s something to be said for the multiple facets on which this semi appeals.
It’s big, it’s fast, and it’s got an awesome interior too – not all vehicles can score so well on so many different fronts.

We’ve seen a lot of impressive semis out there too.
Remember the Ford van that someone transformed into a 6-wheel mini semi?
And of course there’s the long awaited Tesla Semi, which has a battery heavier than an entire Cybertruck.
Ben joined Supercar Blondie in February 2025 after being published by international organizations including LADbible, The Sun, the New York Post, and the Daily Mail. He covers supercars, rare and collectible vehicles, aviation, luxury assets, and the fascinating people behind them. His reporting has explored everything from seven-figure supercars and historic Ferrari collections to unusual aircraft adventures and extraordinary automotive discoveries from around the world. Ben has also gained first-hand insight into vehicle craftsmanship and customization, including visiting specialist workshops to see bespoke vehicles up close.