Preventative maintenance tells us that at over 20 years and 150,000 miles with NO records, you are past time to change the long 560 timing chains, the tensioner and the guide rails.

In fact I do it every 100,000 miles (or 10 years).

The risk is not worth it, if the chain lets go (usually more often it happens on the left side) there can be a horrible disaster. Better be safe than sorry.

This is also the time after the valve covers are removed, to also check the cam oilers and injectors and replace those if needed.

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)