These fluids are for the BTR axles, Salisbury are different.- see below from GOMOG site
The recommended oil for a LSD Salisbury (Plus 8s & 7HA and 12HA) is a 80/90 Hypoy oil for limited slip differential (LSD) axles (for example;
1. Castrol Hypoy LS90
2. Mobilube Mineral LSD 80/90
3. Royal Purple 80/90 LSD
4. Valvoline
5. Mobil 75/90
Capacity
4/4s Imperial Pints 1.3-1.4 liters Castrol SMX
Plus 4s 2.5 Imperial Pints 1.3-1.4 liters Castrol SMX
Plus 8s 2.5 Imperial Pints 1.3-1.4 liters Castrol Hypoy LS
The recommended oil for a non-LSD Salisbury (4/4s and Plus 4s) is now Castrol 75/90 or its equivalent. Salisbury axle fluid should be ideally changed at 3000 miles intervals. One cannot exaggerate the need to be careful. Never mix old and new oils. Some of the newer dealers suggest what they believe to be modern synthetic equivalents. However, the Salisbury's are not noted for strength and parts are no longer made. A chipped Crown Wheel and/or Pinion will and has sidelined many Salisbury Morgans indefinitely, though they can be had with GREAT DIFFICULTY. As Salisbury's original recommendation has worked for 60 years, there is no logic in taking risks. A BTR can be fit, but MMC waiting times run into many months for a BTR and it is no longer known whether Classic Morgans will be supplied since these models have been abandonned. The cost of the axle and labor to remove the hubs, swap and weld the brackets and install a new BTR will cost £4000...unless the work is done by the owner and he is VERY lucky in their part sourcing.
