Artificial Stupidity: In the base game there is no AI at all. If you download the patch, the opponent rig will move... and then stop short of the finish line because there is no code for what happens when you lose a race. If anyone but the player happened to win, the game would crash.
GameSpot reviewer Alex Navarro kept his rating within bounds. He commented that the only reason the game received a 1.0 out of 10 (the lowest score ever given by GameSpot) was because they couldn't go any lower. His video review grants the "No. Just... No" Reaction rating as well.
Net Jack apparently rewrote its code so it could award the game a zero.
X-Play refused to rate the game. They didn't have a zero, and they were unwilling to give this game anything higher. As such it never received an actual review, but it was spotlighted in a segment on games that would have gotten a zero if allowed.
The Angry Video Game Nerd is reduced to corpsing at the most egregious flaws, particularly at the "YOU'RE WINNER!" screen. He called it the most unplayable game he's ever reviewed.
A common problem that reviewers who tried to review Big Rigs have had is that, to even review it under normal constraints, one must acknowledge that it is in fact a game. Big Rigs commits so many violations of what should be allowable in any gamenote driving through what should be solid objects or being absolutely impossible to lose that it becomes difficult to categorize as a game more than it is a very incomplete and work-in-progress game engine with a few assets that somehow ended up on store shelves. As such there is no metric that can sufficiently describe it.
Covers Always Lie: A truck with flamesnote no vehicles move anywhere approaching this fast when traveling forwards spouting from it rammingnote no collision detection a police carnote no police with the tagline "18 Wheelsnote not all trucks have loads and are 18 wheelers Of Thundernote no SFX." Even the concept of this game as carrying cargo is debatable, as all vehicles end where they start. The back of the box◊ has advertising so blatantly false you'd almost think it was a satire. It mentions "features" such as "three levels of difficulty" and avoiding police, neither of which are in the game. The screenshots are also obvious mockups if you have seen any actual pictures of the game. The most laughable thing, however, has to be its mention of the AI that will supposedly challenge the most experienced driver (hint: read the rest of the page). About the only thing it actually gets right is the environments it lists off, and even that's making an exception for the track that will always cause the game to crash when it's selected.
You absolutely can't lose. Even if you download the patch to make the opponent rig move, it still stops short of the finish line. If it did somehow cross it, it still wouldn't win because there is no programmed failure state.
Sometimes the game's code has trouble distinguishing between starting and finishing, so you might win the race the moment you begin.
Game-Breaking Bug: It would be easier to count which things work properly than things that don't.
Ludicrous Speed: Just how fast can your truck go in reverse? It depends entirely on how long you're willing to keep your finger on the Down Arrow or how long the game can run without crashing.
The Mockbuster: The game has "18 Wheels of Thunder" on the bottom of its box. This could be seen as an attempt to fool people into thinking that it's an entry in the 18 Wheels of Steel franchise due to how similar the two titles are.
Obvious Beta: And a buggy one at that, as shown by other examples on this page. For the sake of perspective: programming-wise, this "game" represents less than a day's work for an experienced game developer. In a desperate further attempt to pass it off as a real game, the devs released a patch fixing the opponent trucks' immobility and a broken map... and nothing else. And the opponent trucks now stop before they reach the finish line, and the "fixed" map only turned it into a mirror of the first map.
The game is completely devoid of collision detection, and aside of the ground itself, you can drive through anything you encounter. This includes even bridges, which should allow you to drive on them, but instead you just sink into them and drive on the bottom of the dry lake.
The game is an utter memory vampire - if you pull up Task Manager, you'll see that the game somehow uses 50% of available memory, way more than it should.