the problem isnt with the timing chains themselves.. it resides in the guides for the timing chains, primarily the one or two on the front end of the engine. the guides break off over time and cause the chain to rattle a little bit. This has no ill effect on the engine, just makes an annoying sound on a cold start and in the higher rpm's.

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2001 Ford Ranger Supercab (4dr), Oxford White, 4.0 Sohc, 4x4, Manual trans (hurst equipped), 4:10's, 3" body lift.