Hello everyone I have a 2009 f150 with the 4.6 in it and 180,000 miles. The heater works great, the system pressure tested great, there is no smell inside the cab or leaks. I have a 6" adapter hooking the inlet side nipple to the actual hose that has a drip. There are a couple o rings on each end of it. I replaced this 6" piece hoping to stop the leak. It didn't. Truck runs great except blows a little steam from the hood due to the antifreeze dripping onto the exhaust manifold. Seems like if I could stop this leak, everything would be fine. But today the dealer replaced this 6" piece bc they said that's the only leak or explanation they could find. Well it leaked on them too. Square one again. Any ideas? They also said they did a coolant flush. Flabbergasted to say the least... Thanks for any response!

 

Ran into this problem a couple times when working at the dealer, the problem being the replacement O-rings, they are not the same size as what the truck came with, you will want to take the old O-rings with you to a place that specializes in hose repair and have them matched up. In the few cases I had I was able to reuse the old O-rings with great success.
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