Hi Dave, thanks for the reply. I've only had the car for 2 weeks and so far it's running good, i could probably diy-it but I've not done it before so the missus won't let me🤣( it's her car) . Local BMW dealer quote me 830£ for gearbox service and 550£ for transfer box/boxes service. Safe to say I told them I'll sleep on it for a bit😁