Nice to see another Defender being used properly. We did a similar trip two years ago in our 110 and it also never missed a beat right until the last 100km, when the Tom Wood Double Cardan propshaft managed to destroy a universal joint.
We also destroyed the the BFG KM2 255/80R16 rear tyres, they lasted about 20,000km and we bad enough that we had to change them over in Carnavon to a pair of Maxxis Bighorns. We had 2 ton on the rear axle when we took it over the weigh bridge fully loaded , and 1.4 tons on the front with just the two of us. What tyres did you run on your trip?
I've done another 12,000km since then on a Bighorns including coming back from Steep Point to Cape Byron across the middle and they still look good. They are our touring set, and we only fit them when we are going out, otherwise the OEM Continentals over used around town and to the beach.

