Hi, all. New here. Have a 2000 F150 with 5.4L and 80k miles. It is losing coolant into the motor and running very rough. Mechanic says not likely a head gasket or cracked cylinder head because very uncommon on the Triton's.

He said that when the PH level of the coolant goes out of balance it tends to eat through the intake manifold gasket...

Coolant than leaks into the intake port.

Has anybody heard of this??

Todd

 

Head gasket problems are a concern on some mod motors, but these mostly manifest themselves as oil leaks.

What he's describing is electrolysis...the coolant reacts with the aluminum in the engine and becomes an acid. Normally, this will kill heater cores and radiators before base engine components though, weakest link and all.

 

Old/bad coolant can lead to all sorts of maladies. Best to change it regularly.

"Most likely" seems a bit of a guess. Those repairs you note are not cheap, I'd try to make sure you know exactly what's up so that you aren't wasting money.