I've been seeing a lot of videos about the infamous Panzerkampfwaken VI "Tiger I" and how it's apparently extremely unreliable and how everything it did was a failure, among those statements there's a reocurring "transmission bad" meme that's embedded against the tank.
I can't help but doubt the legitimacy of that meme considering that a lot of tanks in WW2 had transmission problems and most of the sources that were used in the testing of the Tiger was done by Soviets. So was the tank really a failure? Was it as bad as it is stated or does it's infamous glory have some sort of merit?
The British (who conducted their own Tiger tank trials) didn't have an exceptionally high opinion of the Tiger's reliability either. Even with the first Tigers, you already see criticism of the complexity of the design.
“The tank bristles with every sort of complication, and one would think that it would be at least twice as difficult to produce as either of its predecessors. This may have a bearing on the numbers that are likely to be met with in the future and the degree of dilution by Mk.III’s and IV’s.”
Full scale reliability trials of the Tiger 131 were not performed, to my knowledge, but the British do note that the tank's engine broke down twice in the exact same way during gunnery trials (which aren't particularly tasking to the engine group).
The Tigers' mechanical performance in Italy was not much better. The British came across many tanks with mechanical breakdowns (particularly the transmission and suspension) and noted that the Tiger crews they face tend to retreat even in cases of minor danger, since even light damage could put the Tiger out of action and render it irrecoverable.
In June of 1944, after examining the Tiger's performance in Italy, the British concluded:
“Tiger is not yet sufficiently developed to be considered a reliable vehicle for long marches.
He suffers from frequent suspension defects and probably, also gearbox trouble.
When pushed, as in a retreat, those troubles are too frequent and serious for the German maintenance and recovery organization to deal with.
Tiger killed himself.”
You may note that the statement "not yet sufficiently developed", but the Tiger had already been out of production by that point, meaning that it would never become "sufficiently developed". Statements collected from German POWs in Normandy confirmed that this tank, much like the Panther, suffered from considerable engine and running gear defects (although the transmission is not mentioned).
Even if you disregard data gathered by the USSR, the Tiger is described as very unreliable by British specialists throughout the course of WW2. Whether or not you want to consider the tank a failure because of this (or other factors) is a much larger question.
Sources:
https://warspot.net/156-tiger-killers
https://warspot.net/411-tiger-tiger-burning-bright
Canadian Military Headquarters, London (CMHQ), Files Block No. 55 - 5777 image 2320
Canadian Military Headquarters, London (CMHQ), Files Block No. 55 - 5777 image 2199
I don't know what to tell you. It was a heavy tank and one that underwent relatively gradual changes and updates throughout its relatively short service life. The original engine was under-powered but that really only affected the first production run of 250 tanks or so before it was changed. The interleaved road wheels were a problem in certain conditions but overall it was a reasonably solid tank. I would argue it wasn't significantly better or worse than other contemporary tanks in terms of reliability.
That said, as with any heavy tank they are a logistical nightmare and a maintenance and supply guzzling beast but that is not unique to tigers, it's applicable to all heavy tanks of the era and one of the chief reasons the M-26 never saw more service. A good example of why the Tiger I gets a bad rep is the interleaved road wheels. They're great for evenly distributing weight and the germans used this design a lot on everything from tanks to half-tracks and even tracked motorcycles like the SdKfz 2. None of these have a particular reputation for reliability issues but the Tiger I does, even though the principle for maintaining them is virtually identical. Because none of the other vehicles weighed in around 55 tons. With a vehicles that heavy, everything is heavy and maintenance is exponentially more complex.
Aside from this and some teething problems surrounding the engine and transmission the Tiger I was generally mechanically sound. It required a lot of maintenance but so did any comparable tank, when something breaks on a heavy tank it is relatively more difficult to fix it because of the weights involved. A Tiger I or II required two, sometimes three Famos (Sd.Kfz 9) to tow it instead of one for most contemporary tanks but this is result of the weight of the tank, not a flaw in its design.
In broad terms it was roughly in the middle of the pack in terms of how many were combat effective at any given time in both theaters, slightly below the various Pz. IV's, slightly above the Panther. Overall, a decent german tank in terms of reliability.
Edit: Oft quoted versions of "The german tanks can be used until they break down" are sometimes attributed to the Tiger and it's probably true but this true for an enemy operator of the tank who does not have access to the specialized skills and tools required to maintain a heavy tank. It is not true for germany.