Thank you very much for the explanation. Can the car be ordered that way or has the axle to be modified afterwards? And how much would that cost?
I don't know how much it would cost to have a 3.7 diff converted to 4.11. In theory it's quite straightforward, as it should be just a question of changing the 10-tooth pinion on the input shaft for an 11-tooth : The crown wheel stays the same at 41 teeth, giving the higher ratio (41/11 = 3.73) as opposed to 41/10 = 4.1.
Having said that, if you were going to go down this route I would heartily recommend having the differential itself replaced with a Quaife torque-biasing unit, with these you get all the advantages of a limited-slip differential without any of the disadvantages of a locking arrangement. I had this done to my 4/4 and it has transformed the ability to get power down effectively.
But it's not cheap, I think I ended up paying Billy Bellinger way over GBP1000 to rebuild my rear axle. Mind you, he did a splendid job.
