Wife got the low coolant warning yesterday. The bottle is low. There is no sign of leakage anywhere including the crossover pipe under the intake manifold. Any suggestions?
If your not adding coolant on a regular basis, then it might just be air leaving the system over time. If you would call this a constant, unexplained loss of coolant. Then yes I have some suggestions. And if you find what I'm going to tell you about, I suggest you go to Walmart and buy a 4sale sign.
The cylinder block on the right side has a cavity that is just space. It's behind the rear cylinder on the right bank. I have had more than one 5.0 that was leaking coolant into that chamber to noplace. The area is enough to hold a small amount of coolant and everything else is pushed out a hole that accepts a fur tree style fastener holding a wire harness to that side. So just like all those cylinder head outlet pipe leaks that get missed. This leak is really hard to find. Every time I have ever seen coolant get into that area and weep out the fur tree fastener hole it was because of headbolt threads being pulled out of the block. A couple times they made me fix the blocks. Helicoils in the bolt holes. After about a year one of those trucks came back with threads pulled out of the other head. So if I was going to fix one again I would probably want to pull both heads and fix all the holes. Once a 5.0 gets hot its a boat anchor. A new 5.0 still cost about $28,000.
Talking about the outlet pipes you guys are starting to talk about. The front one that sits under the throttle and behind the water pump is called the cylinder block outlet. The one on the rear of the engine is the cylinder head outlet.