Going on from this, I wonder if there is more merit in putting some lube on the rear of the wheel than the lug. I shall explain, once upon a time the garage had to replace a tyre for me, once the wheel lugs had been removed the wheel decided to stay attached to the hub. Apparently, with the wheel being aluminium and my constant cleaning routine at the car wash, the wheel some how bonded itself to the hub. After several good wallops on the back of the wheel with a club hammer and lump of wood the wheel finally parted company. According to the garage chap it would be prudent to put some copper grease on the back of the wheels; this he done to all of my wheels for no additional charge bless him.