The speed sensor is in the rear diff.

Speedometer pick-up, adjustment and sealing
Note! (Type 1030/1031 rear axles with 12 tooth wheel, refer to specifications for correct clearance Specifications ).

Adjustment of clearance
Permissible clearance: 0.85 ± 0.35mm (0.0335 ± 0.0138 in)

Remove oil level plug on inspection cover

Insert 0.85 mm (0.0334 in) feeler gauge between pick-up and toothed wheel. Turn pinion
-1. Shim
-2. Place shim between pick-up and inspection cover
Move feeler gauge forwards and backwards. Measure with progressively thicker gauges (in steps of 0.1 mm/0.0039 in) until gauge catches between pick-up and toothed wheel. Note clearance.

Remove and measure thickness of existing shim under pick-up
Undo pick-up nut with box spanner.

Calculate new shim thickness
Example:
Measured clearance1.25
Permissible clearance-0.85
Difference0.40
Example:
Existing shim1.60
Reduction-0.40
New shim1.20

Shims are available in thicknesses of 0.5 to 3.0 mm (0.197-0.1181 in), increasing in steps of 0.1mm (0.0039 in).

Install pick-up and new shim
Recheck clearance.

Refit oil level plug
Sealing
Pick-up must be released if removed.

Before reconnecting connector:

Thread sealing wire through connector cover
Connect connector to pick-up

Thread sealing wire through locking tab on connector and clip on pick-up

Thread lead seal onto wire and crimp with pliers.

Regards Peter