Tow bar

I don't know the ramifications with the X3 M, but way back when buying a new X5 [ was 2005] there was more, officially, to towing than bolting on a towbar, electrical harness and telling the onboard computer.

The factory fit included then an up specced cooling system, in part accounting for the huge option cost.

I am well aware some simply just add a towbar etc, but the maker requiring a change to the cooling system hints there is an underlying reason for that.

If you are going for an X3 I would recommend against the M Sport. The suspension is hard and uncomfortable towing or solo. Go for the SE or X Line and think of a 3.0D. It’s more economical than the 2.0D of the previous range. It’s an absolute dream of a car.

if you go for a BMW towbar you won’t get the charger and fridge wires connected (the Alko circuit works ok). Don’t worry about this as the car’s regenerative systems and stop start mean that those two circuits aren’t permanently live anyway.

The only time this may be a problem is if you stay for a period on a no mains pitch and leave with a low caravan battery charge. You may not have enough power to move the van onto your pitch on arrival.

No change needed to cooling system.