Relevant cracked article. (See #5)

The hyperlink is contained in this line:

Early tank models were about as durable as moist toilet paper, and used to catch fire more often than a Catholic church in Norway.

Here's the article they cite as a source.

The source starts off with the appealing title of "The M-4 Sherman Tank Was Hell on Wheels — And a Death Trap." And of course, the source quotes Belton Fucking Cooper. The article itself reeks of oft-repeated myths and German propaganda:

Most tanks at the time ran on diesel, a safer and less flammable fuel than gasoline. The Sherman’s powerplant was a 400-horsepower gas engine that, combined with the ammo on board, could transform the tank into a Hellish inferno after taking a hit.

Hence, the Sherman’s grim nickname—Ronson, like the cigarette lighter, because “it lights up the first time, every time.”

So, this previous badhistory post by /u/Thirtyk94 has already covered myths surrounding the Sherman. I'll just quote relevant bits from it to explain how fucking stupid this whole article is. For one, the myth of Shermans easily catching fire was due to the poor placement of ammunition, which was later rectified, and is nowhere near as ridiculous as the source states it is:

Now the Ronson myth does however have a bit of truth to it. Early Shermans had very vulnerable ammo racks which were stored in the "humps" near the front of the hull. The placement of these ammo racks made it easy for German gunners to know where to hit for catastrophic kills on the Sherman tanks. The army knew of this problem and moved immediately to fix it. The army developed "wet" ammo racks which involved putting the ammo racks inside of water filled jackets to douse any embers or fires immediately, and they also moved the ammo racks to the bottom of the tank to reduce the chances of them being hit by AT weapons. Wet stowage reduced the chances of an ammo rack fire or detonation in Sherman tanks to only 15% compared to 60-80% of dry stowage Shermans. The conclusion on the Ronson myth is that while there is truth behind it, the myth has been so overblown as to rival the invulnerability myth of the Tiger.

Oh, and speaking of the "invulnerability of the Tiger"....

All it took was a German adversary like the awe-inspiring Tiger tank with its 88-millimeter gun.

From wikipedia:

While the Tiger I has been called an outstanding design for its time, it was over-engineered, using expensive materials and labour-intensive production methods. The Tiger was prone to certain types of track failures and breakdowns, and was limited in range by its high fuel consumption. [...] It was also difficult to transport, and vulnerable to immobilization when mud, ice and snow froze between its overlapping and interleaved Schachtellaufwerk-pattern road wheels, often jamming them solid. This was a problem on the Eastern Front in the muddy rasputitsa season and during extreme periods of cold.

Not sure if you want to call a tank with so many reliability and maneuverability issues "awe-inspiring."

The loss of both men and machines is hard to grasp. Simply put, in the heat of battle it was as dangerous inside of a Sherman tank as it was outside of one.

Hold on a minute.

Thoushaltbemocked pummels his face with a sledgehammer.

Just....how the fuck can you be this fucking stupid? There's a fucking reason that 49,234 M4 Shermans (plus 4542 M4A3E8 variants) were built; the Shermans were good at what they did. The allies wouldn't have used so many if "it was as dangerous inside of a Sherman tank as it was outside of one."

(Edit: As this video explains, the % casualty rate among armored vehicle crews in the US army was 3%. (1,407 KIA 167 DOW out of a total of 49,516 troops) This was significantly lower than the % casualty rate of infantry, which was 18.5%. (120,111 KIA 19,799 DOW out of a total of 757,712 troops) Statistically, you were less likely to die in an armored vehicle in the US army during WW2 than you were to die in an infantry position. Thanks to /u/GrassWaterDirtHorse for linking this video in the comments section.)

“The 3rd Armored Division entered combat in Normandy with 232 M-4 Sherman tanks,” writes Belton Cooper, author of the appropriately named Death Traps, a study of U.S. armored divisions and their battles in Europe during World War II.

“During the European Campaign, the Division had some 648 Sherman tanks completely destroyed in combat and had another 700 knocked out, repaired and put back into operation. This was a loss rate of 580 percent.”

(Edit: As /u/Enleat and /u/NotExistor have pointed out in this thread, not only is the "loss rate of 580%" absurdly terrible math, but the number of Sherman tanks used for the "European Campaign" was pretty huge, in the tens of thousands. If we put that factor in the denominator and put the 648 destroyed 700 knocked out factor in the numerator, the actual loss rate is far less than the stupid claim of "580%")
As /u/blefuscuer pointed out, there's a bit more to the whole thing.

Oh god, and just when I thought it couldn't get worse, the source cites Belton Cooper, a man whose work was full of flaws. Here's just a few:

Instead, the reader is subjected to Mr. Cooper veering off into stories he had heard second hand or into broader topics only loosely related to his experiences. For example, the reader is forced to endure Mr. Coopers opinion on everything from German V2 rockets and jet fighters to General George Patton’s (supposed) influence on US tank design.

Another aspect of the book that becomes rather frustrating is the authors frequent and persistent hyperbole. Everything is overstated. For example, when the author witnesses an aerial battle between US bombers and German fighters, it is described as “the most spectacular aerial battle of the war.” His admiration for the German opponent seems to know no limits, referring to the German General staff as “brilliant”

As to the M4 Sherman tank, his penchant for hyperbole extends fully into the opposite direction. The M4 Sherman is not just inferior to German tanks, it is “tragically” and “vastly” inferior. According to the author, the decision to concentrate production on the M4 was “one of the most disastrous decisions of World War II, and its effect on the upcoming battle for Western Europe was catastrophic.”(page 28) Later, he adds to this sentiment, stating that if US forces had been equipped with a better tank during the November 1944 offensive, “The battle of the Bulge may have never taken place, some 182,000 German and American casualties might have been averted, and the war could have ended five months earlier.” (page 155)

In regards to the main thesis of this book, that the M4 Sherman was a “death trap”, the author relies on a fairly narrow sets of figures and anecdotes, which he repeats multiple times throughout the book. Unfortunately, his writings display a surprising level of ignorance about the weapon systems of which he speaks. Names and designations are repeatedly misidentified, and basic information regarding the performance of various weapon systems are presented incorrectly. Granted, in most soldier memoirs, errors on technical matters are bound to crop up. This is expected and forgivable. However, Death Traps is not just a soldiers memoir. It is an intentional indictment by an ordnance officer concerning the primary piece of equipment he was charged with being responsible for. Therefore, one would expect more care to be taken to ensure that the facts presented regarding the subject of the book would in fact be correct.