Monday 23 October 2017

Sherman Engines

Things like fuel efficiency and average speed don't really come up much in most tank encyclopedias, which is a shame, since these are very important characteristics in the real world. The Americans, in their investigations of a new engine, were kind enough to provide these figures for a few Sherman tanks for us.

RG 24 C-2 vol 12290 1/TK CRUISER/1

These numbers are interesting on their own, but let's compare them numbers obtained in Soviet trials

The M4A2(76)W consumed 330 L of fuel per 100 km of beaten road driving, or 0.71 mpg. This seems consistent with these figures, falling in between highway and cross-country. The regular M4A2 in the Soviet test performed twice as well (although it had a higher quality road to drive on), even beating out the Western M4A2 in fuel efficiency. 

On the country, the M4A2 consumed 246-268 L per 100 km (0.87-0.9 mpg), depending on the season, and the M4A2(76)W consumed 371-410 L (0.57-0.63 mpg).

The higher fuel efficiency could be explained by the fact that the Soviet drivers just weren't gunning the engine very hard. Even at their fastest, the M4A2 put out 22.4 kph (14 mph) in the winter, and the M4A2(76)W achieved 19.2 kph (12 mph) in the spring, much worse than the M4A2 seen here.

Since the Lee is from the same tank family, let's throw it in here as well, from earlier trials. The tank spent 297 L per 100 km of stone road (0.97 mpg), 440 L on a dirt road (0.53 mpg), and 570 L off-road (0.41 mpg), which is comparable to the tanks seen here. The average speeds were 26 kph (16.1 mph), 17 kph (10.5 mph), and 12 kph (7.5 kph), respectively. Comparing it to its closes relative from the Canadian data, the M4A1, paints the same picture: the Soviet drivers were more fuel efficient, but also slower.


  1. There is more things to compare between tank engines. Engine torgue and its performance with tanks would be more interesting to me, as tanks had petrol and diesel where should be a big differences in this parameter on the same power engines (maximum power).

  2. The M4A2 was a diesel engined tank. Diesel has a higher specific energy per gallon, the thermal efficiency of diesels are higher and there is no throttle losses. That's why the M4A2 was able to drive further on each liter of fuel than a comparable power gasoline engine.