Its a long shot but if there is no mayo to speak of, and the exhaust isn't pouring out water, then it could just be a simple problem of an air lock.
When you start the engine from cold, it is not unusual to see spits of water coming from the exhaust. That is condensation. But if you are losing water, and its not in the oil, then get someone to drive behind you to keep an eye on your exhaust for water. Water in the oil could mean either head gasket or oil cooler gone.
Water out of the exhaust will mean head gasket, or extemely rarely, holed water jacket.
If you suspect an airlock, then remove one of the water temp sensors in your top hose connector and slowely fill the tank again, every now an again squeezing a hose.