At PDR Differential and Driveshaft Centre, we have the full workshop facilities to handle all fitting requirements. We can recondition or repair most vehicles, including:

  • Passenger Cars
  • Light Commercial
  • 4WD Diff Assembly
  • Industrial and Forestry Vehicles
  • Off Highway Vehicles
  • Roadwork Vehicles

Our Differential services include:

  • LSD (Limited Slip Differentials)
  • Locking Differentials
  • Ratio Changes

About Differentials:

A “Diff” has 3 operations to perform in your vehicle.

  • To help in the transfer of power to the wheels.
  • To determine the final gear ratio between Engine & Wheels. The Ratio is determined by the number of teeth on the Crown Wheel and the Pinion. For example, 41 Crownwheel teeth divided by 10 Pinion teeth = 4.1 Ratio. 
  • To allow the wheels to turn at different speeds when handling corners. As the vehicle starts to turn, the axle & spider gears start to move. The inner wheel will turn slower than the carrier; the outer wheel will turn faster. The drive is transferred by the crown wheel and pinion through the spider gears, axle gears, axles and to the wheels. The Axle Gears and Pinion Gears allow the wheels to travel at different speeds as you turn a corner. In a straight line, the pinion drives the crown wheel & carrier and none of the spider gears turn. Both axle gears spin with the carrier.


Types of Differentials:

L.S.D (Limited Slip Differential)

Limited Slip Differentials are traction devices that are beneficial when towing an extra load. They give you the extra drive you need when pulling your boat, caravan or trailer.
An L.S.D has the same components as a standard Diff Assembly with the addition of a spring pack and a set of clutch plates or a cone clutch. The springs push against the clutches creating a load. When one wheel spins faster than the other, the clutches try to fight this and try to turn both wheels at the same speed. For the wheels to turn at different speeds the wheels must overcome the break-off torque of the clutches.

We can supply & fit Limited Slip Diffs to most vehicles for street application to create some extra traction when required. Standard & Heavy Duty Units are available for some applications.

Locking Diffs:

Serious off road and performance vehicles are sometimes fitted with Locking Diffs where a Total Locking Device is required. These have an electric pneumatic or hydraulic mechanism to lock the side gears to the carrier so you will have a positive lock and the wheels cannot turn at different speeds. In extreme circumstances, if one wheel is lifted off the ground, the locking mechanism can be engaged so you can still get the drive to the ground.

We can supply and fit air or mechanical lockers as well as Spider Gears, Side Gears, Crown wheel & Pinion Bearing Kits and Axles. We carry all major brands including ARB, TJM and Detroit, and our mechanics would be happy to recommend the best brand based on your specific vehicle and requirements. Give us a call or stop by the workshop.

Ratio Changes

Do you require quicker take-off, lower revs on the highway, or a ratio change to match your Race Day requirements? We can change crown wheel & pinions to affect the ratio and achieve required results. At PDR Diff, we can calculate the rev increase, or decrease (given tyre size, ratio, speed) that the ratio change will make. If a standard set of gears cannot be used, we can perform a differential conversion. Contact Us for more info.