Different ring/pinion gear tooth counts are involved:
37/9 tooth gearset = 4.1111111
41/10 tooth gears = 4.1000
I believe the Dana rear axles used a 41/10 gearset. The Eaton gears are 37/9.
Jerry
Jerry that makes perfect sense. My problem was with the quote from Denny, which has now been retracted, saying that there "never" was an Eaton HO 52 with a 4.11 gear set. I believe I have linked documentation above that clearly shows a cross section of an Eaton HO 52 (5200 lb axle) with available ratios of 4.11 and 4.57 in the 1966 info packet.
