Salisbury Axles

To dissassemble:
(see diagrams at diagram I and diagram II.

The hubs are keyed on tapered half-shafts (interchangeable). Taper roller bearings in axle tube ends are retained by back plates with shims  behind (.003, .005, .010, .030 in thick) to adjust end float (.006 - .008 in). The inner ends of the half-shafts butt on a floating thrust block around the planet bevel spindle.

To remove the half-shaft, draw off the hub, detach the brake back plate assembly with lipped oil seal in housing and shims. Draw out shaft and bearing carefully through inner oil seal (lip inwards).

The bevel pinion shaft is carried in taper roller bearings. The outer races are pressed into the final drive housing from the front and rear. Shims (.003 ,005, .010, .030 in thick) are used between the shoulder on the shaft and inner race of the front bearing for bearing adjustment. Shims (003, .005, .010 in thick) are used between the outer race of the rear bearing and housing for mesh adjustment.

The pinion setting marked on the face of the pinion (bottom figure of four sets of figures) may be zero, plus or minus. This indicates amount in thousands above or below nominal distance (2.000 in) of face from centreline of the crown wheel. Use mesh adjusting shims to obtain the setting marked and assemble pinion in bearing with the original bearing shims, but without the oil thrower or oil seal. Tighten the driving flange nut and test for preload 18—1 2lb/in).

The crown wheel is spigoted and bolted to the flange of the one-piece differential cage. Side bevel gears run directly in the cage with flat thrust washers behind. Planet bevel pinions have spherical thrust washers and run on the spindle retained by a pin peened to lock. Axle shaft thrust block round spindle.

The differential assembly is carried on taper roller bearings in split housings with shims (.003, .005, .010, .030 in. thick) between the inner races and the cage for bearing and mesh adjustment. Install the differential assembly without shims and with bevel pinion removed and mount a dial gauge on the axle casing with button against back face of crown wheel. Move differential assembly to one side of the housing with lever and set gauge to zero. Lever assembly over to the other side and note gauge reading (A). This figure indicates the play in the bearings and the thickness of shims needed to take up play. Add .004 - .006 in to total to give preload. This total must be divided to obtain correct crown wheel mesh as noted below.

After installing the bevel pinion, reassemble the differential, again without shims. Lever it away from the pinion, set the indicator to zero and lever assembly towards pinion. Note reading (B). This, minus the backlash figure etched on the crown wheel is the thickness of shims to go behind the crown wheel side bearing. The remainder of shims from total (A +.004 -.006in) go behind the offside bearing. When the assembly is complete, check for backlash (.004 in minimum). Change shims from one side to the other of differential bearings if necessary.
 
 

N.B. In Salisbury axles, the carrier is integral with the axle housing. A removable cover at the rear, gives access to the final drive components. The crown wheel is held in the carrier in a similar manner to the removable carrier type, but shims between the housing and the differential case bearings, allow the pre-load setting and backlash to be adjusted.

The pinion has a collapsible spacer for pre-loading, and depth-of-mesh shims for positioning with the crown wheel.

In light vehicle applications, the wheel end of the axle shaft is normally supported by one bearing in the axle housing.

This is called a semi-floating arrangement: the axle shaft supports the vehicle mass, and transmits driving torque.
 

N.B. Please be aware that parts for Morgan Salisburys are no longer being made (for many many years). In most cases, the best solution is an axle swap, the easiest being to a later BTR. Some parts can be found through Morgan Spares in the USA but others, such as the Plus 8s' vulnerable crown wheel and pinion are impossible. The  recommended source is the very proficent Billy Bellinger at J.B. Sports) 

 
QUAIFE, the famous UK differential specialist, does a replacement LSD differential for the Plus 8 7HA Salisbury axles that incorporates the latest Quaife technology.