Ford F-350 Super Duty Problems

One or More Spark Plugs May be Ejectioned From the Cylinder Head on Ford F-350 Super Duty

Problem Description and Possible Solution

The Ford F-350 Super Duty has known issues with the V8 engine ejecting spark plugs. This will make a tapping or knocking noise, plus the engine will begin to misfire at all speeds. The check engine light will also illuminate.

The threads on the cylinder head are too short and soft, allowing pressure from combustion to overwhelm and destroy the threads. 

When the spark plug ejects, the cylinder head becomes damaged, necessitating repair of the spark plug port threads, or replacement of the cylinder head and cylinder head gasket. 

Ford has recommended a method of repair for the cylinder head that prevents the spark plug from ejecting under future use. Replacement of all spark plugs is not necessary, but an updated spark plug design can help prevent this from happening in the future. 

There is a technical service bulletin for the V8 engine.

(10 people reported this problem)

Ford F-350 Super Duty Vehicles With This Problem

RepairPal Verified
Average mileage: 183,333 (150,000–250,000)
Engines affected: 5.4L V8, 6.8L V10, V8
7 model years affected: 1999, 2000, 2001, 2002, more2003, 2004, 2005
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Viewing 1-3 of 3 comments
I have two spark plugs eject #4 and #5 within a year. I have used been using timesert inserts and they have to be changed each time I tune up truck. This is a real pain and this "Flaw" by Ford has really caused me a lot of stress. Now I have a insert and new spark plug spinning and can't see the insert with spark plug in there to tell what is going on!!! I am trying to make my socket extension and ratchett stronger so I can turn and pull with force , no luck yet i am afraid that I will have to pull the head. Help