Old thread, but my 2008 started losing coolant. Started slow, but I noticed steam today. Heater tee broke. Got lucky, just drove a couple hundred miles on a trip.
Had an SAIS CEL that had me under the hood—spotted the leaks just in time. The tees completely disintegrated upon removal. I replaced them with the hose assemblies and OEM clamps - 30 mins taking my time. 2008 Land Cruiser with 250K miles.