i bought some 22" alloys to go on my rrs, with two good 265/35 tyres, i also bought two nearly new 275/40 's as i want to change to this size all round, but what i wanted to know is would i be able to run on two differant sizes at present, or would i have to fit the same all round, can anyone help please

Really On a permanent 4wheel drive vehicle. Your answer is NO. Not unless you want to smash up all the diffs transfer box and gearbox.

Of course, the different diameter wheels would screw your gearbox to bits. On a 2 wheel drive vehicle you would just about get away with it but the handling could be bad and it would be illegal.

The difference in diameter is nearly 5%. I would think that it's enough of a difference for the TC/DSC to constantly cut in because it'll see it as traction loss at one axle.

It's also possibly enough to cause the transfer box problems/get overheated. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

thanks for all your replys that's a no no then