Keep replacing radiators.
2000 F-150 4X4, 5.4L. 300k+ miles and I'm on Radiator #9!!! Used different
brands and all seem to start leaking at the tank seams about 3/4 of the way
down on the right side. No corrosion due to electrolysis. Each time the
radiator is replaced, new coolant and distilled water are added. System has
been pressure tested and no leaks, even at the heads. I have owned the
truck since it was new so I know it hasn't been wrecked. Techs are baffled
and so am I. Any ideas? Thanks in advance.
Maybe too much pressure. Try a cap with a lower pressure rating or replace the one you have with a correct Ford brand cap. I am on my original 2003 F150 radiator with zero problems over 185,000 miles.
On my original 1998 F150 radiator. I wonder if your exhaust is leaking in the cooling system over pressurizing it.
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