Dana 30, 35, 44, 60, etc???

When talking Dana axle/diff assemblies, what does the number 30, 35, 44, etc represent?

Dana Spicer builds differential parts and axle assemblies for auto/truck manufacturers. The numbers are designations for the different models. Dana gives a larger/stronger/higher load capacity axle a higher number. All XJ's and most Wranglers and Grand Cherokees got a Dana 30 for a front axle. A Dana 44 front axle is stonger than a D30 and came on many vehicles including Ford and Dodge 4x4 pickups. Dana 44's front and rear come on the Wrangler Rubicon. A Dana 60 front axle is huge and were in 3/4 or 1 ton 4x4 pickup trucks. Most XJ came with a Dana 35 rear or later on a Chrysler 8.25 rear axle. Some 1987 - 1989 XJ's came with the stronger Dana 44 rear that everybody is looking for. Dana also made D60 and D70 rear axles to match the heavy duty front axles in pickups and to install in 3/4 and 1 ton work vans.