Factual error: Oddball tells Kelly their commander had been trying to get them killed ever since they landed at Omaha (beach). Oddball's tanks are part of the U.S. sixth Armored division (the Super Sixth, as the unit shoulder patch on his jacket indicates) which actually landed at Utah beach on July 18, 1944. (00:30:50)
Factual error: During the scene where Clint Eastwood is trying to convince Don Rickles to join in the heist, there is a box of Almond Joy candy bars behind Don's head. They weren't introduced until 1946. (00:28:50)
Factual error: As Oddball and his motley crew depart with the "purchased" Tiger, Moriarity is standing up in the hatch, fiddling with his cap. Since this is the driver's position, and very cramped, either he is straddling the driver's shoulders, or driving with his feet.
Suggested correction: The tanks used in the film are mocked up Russian T-34's (As mentioned in another mistake) which changes the proportions of the interior. Additionally, in regards to the "cramped" quarters; Tiger 1 tanks are actually quite infamously known by the soldiers that crewed them for having spacious driver, and assistant driver (Bow gunner) positions; with some crew even able to lie down inside of them.
Factual error: At the beginning of the film as the camera follows the security sergeant he taps a man on the shoulder. The man was standing next to the crossroads signs in a camouflage poncho. As he turns, you can see that he that he is wearing jeans and not a standard uniform of the era under the poncho. (00:00:35)
Factual error: The sniper rifle used in the film is a Russian Mosin and were never used by the allies. They should have had a Springfield sniper rifle. The Americans would have had no occasion to "exchange" weapons with Russian soldiers until the end of the war, when they met on the Elbe River.
Factual error: 14000 bars of gold would be hundreds of tonnes, more than the capacity of the one truck. A standard gold ingot weighs 12.4 kilograms. 14000 would weigh 173.6 tonnes. Even if they divided the haul evenly between Kelly, Oddball and the Germans they would be hauling away just under 58 tonnes of gold each, way, way beyond the capacity of anything on the roads in those days.
Factual error: Near the end of the movie the general and the army convoy drive through the town and are stopped by all the celebrating going on. If you look at all the cheering villagers, you can see they are dressed in modern (for 1970) clothes and have hairstyles that were not around in the 1940s.
Factual error: In the final shot of the movie, the Tiger tank/T34 is seen driving away emitting masses of diesel smoke common to the Russian T34. However the Tiger was a petrol tank, not a diesel, as mentioned by the German tank commander. The Sherman was also petrol and well known for its ability to catch fire when hit. It was nicknamed the 'Ronson.'
Factual error: Almost all the German soldiers in the movie are armed with MP-40 SMGs. In fact, most German infantrymen during World War II were armed with Mauser rifles. MP-40s were only issued to squad leaders and officers.
Factual error: The "BAR" carried and fired in the movies is actually a FN-D Model that was never issued by the US Army in WWII. It was developed post war in Europe. Also the Thompson machine guns and the 1919A4s are all firing at a accelerated rate of fire, much faster than normal. This can be attributed to the weapons being blank adapted.
Factual error: During Oddball's raid on the German train station, you can hear a radio playing 'All For the Love of Sunshine' by Hank Williams Jr. Hank Jr. wasn't even alive yet, let alone making records during WWII. The soundtrack to the film also contains the song, "All For the Love of Sunshine," which became the first No. 1 country hit for Hank Williams, Jr. (01:00:10)
Factual error: When the raging Tiger is shooting around we can see that the muzzle brake of his gun stands still although it should be moving back and forth.