Ford 4.0 SOHC
If you looking at getting a Ford with this engine in it from what I seen so far I seen the timing chain components last from 90,000-130,000 miles. So far I have only made this repair in Ford Explorers even know the engine comes in other vehicles Ford makes also. I don't recommend this repair to be done by a basic person do to this repair requires speacial tools that can be costly for a one time use. From what I heard but not sure if it is true the Ford dealer near my shop stay away from these repairs and just install another engine so that may go for other dealers also. In my location for all the parts to do this job it cost around $500-$600 and the labor $850-$950 but can be more depending on the labor rate of the shop. The trouble is there is to much plastic in the cassette assemblies(Chain Guides). In most cases as the plastic starts to fall apart you will hear rattling from the chain hitting the metal form the guides and the engine casing. I have had one when it fell apart a piece of the plastic jammed in the primary chain and caused the tensionor to break and chain to jump enough tooth to kill the engine but didn't cause valve damage.
