The 560 has a real long timing chain, and the generally agreed-upon wisdom tells us to change it out as routine maintenance every 100,000 miles, or in your case, right NOW at 152,000 with no evidence it has EVER been done, at 21-25 years (depending on the year of your 560SEL).

The timing chain slips, on these, most often on the left bank, when the plastic guides, usually the LOWER ones, crack and crumble.

If it lets go at speed the damage is irredeemably catastrophic.


If you hear a rattling noise on startup in the morning, (as mentioned above) even if it goes right away, in a few moments, that is an indication that the chain is about to let go NOW!

The fix is a new timing chain, new upper and lower plastic guide rails, a new tensioner, valve cover gaskets, and while you are in there, I would throw in a set of new injectors and cam oilers, since you are in there anyway already at this point.

Then you'd REALLY be set.

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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)