Why did Ford change the composition of the timing chain tensioner from iron to plastic from 01-02 ? The 2001 has a ratchet that holds chain tension with no oil pressure (fail-safe if OP lost). 2002 model oscillates the chain against plastic guides at every restart until OP is gained.

I have interchanged the tensioners both years and the only noticed difference is the seal on the plastic ones fail early. The iron tensioners do not have a gasket but I did not notice oil loss around it while idling with timing cover off. Perhaps at high RPM's they spray off pressure like the oil pumps do. What are your thoughts??? [...]

Jesse East
Technician
Pepsi Transportation
Roanoke, Virginia, USA