Timing chain issue
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Junior Member
Joined: Nov 2020
Posts: 26
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2007 CLK 350 convertible
Timing chain issue
Hi, a mechanic told me yesterday that my 2013 4matic had rattle noise at cold start and it sounds like time chain issue. The car runs well and I didn't notice anything he said. Maybe it just started showing up now. I googled and found some info about the common issue for W212. Just wonder if anyone has similar experience? The car has about 120k miles. I don't think it will break soon but would like to have it checked to make sure it's OK. I started it a couple of times and couldn't reproduce the metal rattle noise like YouTube. Anyone knows if it can be inspected without major work? I'm thinking to bring it to a local specialist next week. Would 1 hour labor be enough for a diagnosis?
Junior Member
Joined: Jul 2025
Posts: 41
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From: Connecticut
E350 Sedan, SLK320, XFire Roadster
When you do hear the rattle noise, does it occur on a cold start such as a morning startup? Sometimes the valve lifter lubrication oil completely drains during engine cool down. When you restart the cold engine sometimes the rattling or clacking sound is due to the absense of oil on the lifters. When this happens it usually lasts for 1-2 seconds until the flow of oil reaches the lifters. If this is what is happening quite frequently you might be using too low of an oil viscosity. If it only occurs occasionally I wouldn't be concerned. FYI my 2016 E3.5L low mileage engine does it occasionally.
Thread Starter
Junior Member
Joined: Nov 2020
Posts: 26
Likes: 12
2007 CLK 350 convertible
When you do hear the rattle noise, does it occur on a cold start such as a morning startup? Sometimes the valve lifter lubrication oil completely drains during engine cool down. When you restart the cold engine sometimes the rattling or clacking sound is due to the absense of oil on the lifters. When this happens it usually lasts for 1-2 seconds until the flow of oil reaches the lifters. If this is what is happening quite frequently you might be using too low of an oil viscosity. If it only occurs occasionally I wouldn't be concerned. FYI my 2016 E3.5L low mileage engine does it occasionally.
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
THAT'S INTERESTING...
When you do hear the rattle noise, does it occur on a cold start such as a morning startup? Sometimes the valve lifter lubrication oil completely drains during engine cool down. When you restart the cold engine sometimes the rattling or clacking sound is due to the absense of oil on the lifters. When this happens it usually lasts for 1-2 seconds until the flow of oil reaches the lifters. If this is what is happening quite frequently you might be using too low of an oil viscosity. If it only occurs occasionally I wouldn't be concerned.
FYI my 2016 E3.5L low mileage engine does it occasionally.
FYI my 2016 E3.5L low mileage engine does it occasionally.
My new 2014 E3.5L used to rattle exactly like your new 2016 E3.5L before scheduled service.
It turned out it's MB stock oil Euro formula that was causing the low-mileage engine rattling -- So I decided to experiment upgrading to more effective non-stock lubricants... Mobil1 "SuperCar" 5W-50 works better for me without rattling, lag or extreme heat soaks - FAN quit blasting in winter/summer to my satisfaction.
Many ppl believe this is wrong. Many ppl see benefits and many do not.
Start-up rattling is caused by the VVT Phasers NOT being locked. Either by thin oil pressure or worned out by low oil pressure. The lifters are fairly reliable and so are the M276 four separate short chains.
HK Style: AMG with disguised HL
Last edited by CaliBenzDriver; Nov 22, 2025 at 03:10 PM.
