Ok, I just checked some Army doco and all the Military 6x6 are fitted with a Rover type (four pinion) front diff and two Salisbury diffs in the rear axle sets. I had heard that no-spins were fitted to SF vehicles before deployment OS.

I can offer no reason as to why differnt diffs were fitted to some of the early 6x6's but they may be prototypes? I know of several being:

Narrow axles all round (and narrow cab);
Wide rear axles, narrow cab;
wide axle set and widened S3 style cab; and finally
wide axle set and pre production wide cab with modified roof.

Until LR had the ink dry on the drivetrain they may have played will local axle sets as an interim stopgap measure (locally made from local commercial product) rather than setting up a production line for what may have been a very limited model run!!

Many of the prototype vehicles ended up at the Army Apprentice School or RAEME Trainng Centre. One was even sold off by two enterprising apprenti to a local cocky after a couple of litres of mission brown paint. Thing came unstuck for the cockey when it came time to register it butl The Army had listed the chassis and engine numbers on the stolen vehicle register.

As to what type of diffs they are all I can suggest is to look at what was around in 1985 ish when this was on the drawing board.