Fit for: 540i 1997-2003 Base Sedan 4-Door; 540i 1995 Base Sedan 4-Door; 540i 1999-2003 Base Wagon 4-Door; 740i 1994-2001 Base Sedan 4-Door; 740iL 1994-2001 Base Sedan 4-Door; X5 2000-2006 4.4i Sport Utility 4-Door; X5 2002-2003 4.6is Sport Utility 4-Door
A timing chain is the link between the crankshaft and the camshaft that transmits the rotation of the crankshaft to the camshaft, which then causes the opening and closing of the intake and exhaust valves within an engine. The timing chain transfers energy from the crankshaft to the camshaft by wrapping around gears mounted to the ends of the two shafts.
The timing chain can start to stretch and wear over time, which will cause the engine's timing to be inaccurate and produce a few warning signs: 1. Engine misfires or runs poorly; 2. Metal shavings found in the oil; 3. Engine won’t start or fails; 4. Check Engine Light is on; 5. Engine rattles while idling