Difference between a standard and a salisbury axle.

The Salisbury axle casing is made up with a cast centre and tubes so its a different contruction. The Rover axle in mil spec has extra supports welded on, it would be hard to do that with a Salisbury. There are more ratios available for the Salisbury as it was used on a lot of vehicles, its really a Dana so there's a lot of stuff from the States that fits, locking diffs etc. But its not easy to service, the diff is pre-loaded by springing it into the casing with a jack which is one of those fantastic cost effective production line techniques to avoid setting up that cuases much pain in the real world when owners have to work on it. The Rover on the other hand is simple, interchangeable front/rear and can be worked on without special tools, exactly like the rest of a Series.