Kenna a patch of oil in Lane 1 of CTE just into the Cairnhill tunnel couple of weeks ago. Car drifted a bit to the left and I remembered not to apply brakes in such instances. Luckily the following car in Lane 2 was a distance away. Same thing happened to my brother (same lane, same location). Any one else? Dunno if oil is dripping from whatever pipes are attached to the ceiling of the tunnel.