My factory shop manual lists the rear axle oil capacity for the Healey Mark 1 and 2 series at 3 Imperial Pints or 3.6 U.S. pints, but then lists, in parenthesis, 1.7 litres. The litre reference is contradictory to the capacity listed in pints. I didn't measure the amount of oil that came out of the differential, but I have now put two full quarts through the filler hole, and am finally getting a bit of oil backing out. I find I have now put more oil into the differential than is listed for the standard gear box with overdrive, but in this case, as well, there is a much larger number listed for litres (liters to us), 3.6 litres. I'm somehow misunderstanding the capacity listing, or what? I must say the differential is quite large and the filler hole is rather high on it, so it seems implausible that it could require as little as 3.6 U.S. pints to bring it to the proper level.