I have recently bought a 76, and have fitted 285/70/17. It’s making the speedo more accurate and at same real speed, the revs are lower. So I think it’s an advantage. With an aftermarket suspension and the consequent lift of about 75 mm, the size of the tires are not a problem as it’s not touching. About the top heaviness, I can’t comment yet from my own experience but I know for sure that they can take a load, but that may cause a top heavy feel, I think.its simply a matter of weight on top of the car, so I try to get the lightest roof carrier and overall the lightest accessories as weight is any cars biggest enemy. So I plan to drive around 110 max with a full load, to be on the safe side. In my mind a LC 70 series need quite a few improvements/modifications, but then it’s the best, I have seen many of them crossing the dessert effortlessly with a big load, that’s why I wanted one.
Ben Visagie