Salisbury Differentials and Axle Units

Simply Performance supplies and rebuilds a wide range of Salisbury differentials. Though the majority of the differentials that we supply and rebuild originate from Jaguars, they can be fitted into a variety of other vehicles.

The Salisbury axle unit can be used in applications such as TVRs, Aston Martins, AC Cobras, Jaguars, Sunbeam Tigers and Scimitars. Alongside this there is a wider demand for the differential units or complete axles, whether early beam axles or the early IRS (Independent Rear Suspensions), which are used for American muscle cars, hot rods and trucks as well as FIA racing builds or kit car based replicas like the AC cobra. With such a wide variety available you are likely to find specific features suited to your needs depending on your build specification.

Here at Simply Performance we stock a wide range of different Salisbury differentials and axles to suit your requirements. Whether you are a trade customer requiring a number of units or a home builder we would be happy to discuss your needs and find the right solution for you.


We offer a range of different differential services. We can:

  • Rebuild and repair of differentials along with other axle components if needed.
  • Custom build of differentials to order in a ratio or specification of your choice.
  • Rebuilding of differentials to change the ratio or specification.

We also offer many other services depending on what you need. With an extensive stock of used parts we can be sure we can rebuild your differential and supply internal parts if needed. We stock a wide range of crown wheel and pinions. Some ratios can be harder to obtain but the possibilities are 2.88, 3.07, 3.27, 3.31, 3.54, 3.58, 3.77, 4.09, 4.55.



The Salisbury differentials are very dynamic and were fitted from 1950’s until the mid 2000’s. Throughout the years there were a range of different types of cases, ratios and internal setups produced and it is the 4HU and 4HA axles that are mainly found in Jaguars. The LSD (Limited Slip Differential) or PL (Power Lock) unit was a great design and to this day remains one of the more advanced differentials. The PL unit used ramped gears, enabling the pinion cross shafts to move and create more grip on the friction plates. To this day these differentials are used and are in high demand.