radiator leaking

[flonly]

2008 kw t660,cm871,1300000 miles ,100000 miles on rebuild and demandated at mr haggs.Over last couple of days I have been loosing a quart of coolant every night,450 miles on my run.I got back this morning at around 5am when it was dark and with my flashlight I climbed up and tried to look cause I could smell coolant when engine fan was on.There was coolant along the top of the radiator in the front.Not sure yet if its the hose on top,or the neck,or there is a small hose in the front of the reservoir that goes down the front,or could the radiator itself have a break in to top front seam.Anybody have any experience like this?I called a couple kw dealerships and one said no inventory at all in any warehouse and one said orlando has one for 1511.00.anyone tried any aftermarket ones with any luck?thanks