[JRTJH]

If I'm remembering all the information I got from my axle failure, Keystone uses the same "axle tube/spindles" on their 3500, 4400 and 5000 pound axle assemblies. The difference is in the 3500 pound rating, there's small outer bearing and 10" brakes. In the 4400 pound rating, there's larger outer bearing and 12" brakes and in the 5000 pound rating, there's larger inner/outer bearings and 12" brakes.

I don't know if the larger axles are similar or not, but I'd guess the 6000, 7000 and possibly the 7500 pound axle ratings could well use the same axle tube/spindles with similar upgrades to support the increased weight.

I'd suppose Keystone isn't going to spend more money on upgraded components than any other manufacturer. The old phrase, "Industry Standard" for me anyway, just means "they all do it the same way"... (safety in numbers ????)